A clinical guide to the medial ligaments of the ankle: Anatomy, function, diagnosis of injuries and treatment of instability-a narrative review

BACKGROUND

The aim was to provide an update on anatomy and function of the medial ankle ligaments, diagnosis of their injuries and treatment of medial ankle instability.

METHODS

Literature search on PubMed.

RESULTS

Injuries to the deltoid ligament are not uncommon in relation to malleolar fractures and ankle sprains. Chronic instability may lead to ankle osteoarthritis. However, there is no consensus on diagnostic criteria (clinically, by imaging and by arthroscopy), on indications for non-operative and operative treatment, and on standards for repair and reconstruction of the ligament complex. There is no current evidence to support acute repair of deltoid ligament injury. Reports on the effect of isolated deltoid ligament reconstruction are very sparse.

CONCLUSION

There is a need for a focused effort to establish evidence for all aspects of deltoid ligament injury.

Functional performance tests, clinical measurements, and patient-reported outcome measures do not correlate as outcomes 1 year after anterior cruciate ligament reconstruction

PURPOSE

The results after anterior cruciate ligament reconstruction (ACLR) are evaluated by laxity measures, functional tests, and patients' perception by patient-reported outcome measures (PROMs). It is not known, if one of these evaluation instruments is representative or if outcome scores from all must be reported to obtain a full evaluation of the condition. The aim was to study the correlations between these three types of outcomes 1 year after primary ACLR.

METHOD

All adult patients (range 18-45 years) who had an ACLR between 1.1.2019 and 31.12.2021 were offered 1-year follow-up by an independent observer. Preoperative information about knee laxity and peroperative information about the condition of menisci and cartilage were registered. At 1-year follow-up clinical and instrumented knee stability and function assessed by four different hop tests were registered. Patients completed four PROMs (the Subjective International Knee Documentation Committee (IKDC) score, the Knee Numeric-Entity Evaluation Score (KNEES-ACL), the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Lysholm score) and Tegner activity scale and answered anchor questions regarding satisfaction and willingness to repeat the operation.

RESULTS

A total of 190 adults attended the 1-year follow-up and 151 had all assessments. There were only a few positive and weak correlations between performance tests and PROMS and between clinical measurements and PROMS (r = 0.00-0.38), and the majority were of negligible strength. Tegner score had in general the highest correlation (low to moderate). The highest correlation was 0.53 (moderate) between the anchor question about patient satisfaction and Lysholm/IKDC scores. There was no difference in the correlations depending on meniscal condition.

CONCLUSIONS

In ACLR patients there was no clinically relevant correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. Therefore, one type of outcome cannot represent the others. This is an argument for always to include and report all three types of outcomes, and conclusions based on one type of outcome may not be sufficient.

LEVEL OF EVIDENCE

II.

Similar outcomes after anterior cruciate ligament reconstruction in paediatric and adult populations: a 1-year follow-up of 506 paediatric operations in Denmark

PURPOSE

To present 1-year results after all paediatric anterior cruciate ligament (ACL) reconstructions in Denmark (5.9 M inhabitants) for the 10½ year period, 1 July 2011 to 31 December 2021.

METHODS

All children who had an ACL reconstruction were enrolled. They were asked to complete Pedi-IKDC preoperatively and at 1-year follow-up. Independent observers performed pivot shift test and instrumented laxity assessment preoperatively and at 1-year follow-up.

RESULTS

The median age of the 506 children (47.2% girls) was 14.3 years (9.3-15.9). The Pedi-IKDC score increased from preoperatively 61.6 ± 15.8 (mean ± SD) to 85.9 ± 13.0 at 1-year follow-up (p < 0.0001). There were concomitant injuries (to meniscus and/or cartilage) in 49.9%, but these children had preoperative and follow-up Pedi-IKDC scores similar to the scores for children with isolated injury to ACL (n. s.). Instrumented anterior laxity was 4.3 ± 1.4 (mean ± SD) mm preoperatively and 1.4 ± 1.4 mm at follow-up (p < 0.0001). Preoperatively, 3% had no pivot shift whilst this was the case for 68% postoperatively (p < 0.0001). Twenty-five children (5.6%) had 4 mm instrumented laxity or more relative to the unoperated knee at follow-up. Two patients (0.4%) had an operatively treated deep infection, three (0.5%) were operated on for reduced range of motion and two (0.4%) had a revision ACL reconstruction.

CONCLUSION

ACL reconstruction resulted in a clinically meaningful increase in Pedi-IKDC, an improved instrumented stability, a reduction in the grade of pivot shift and the complication rate was low at 1-year follow-up. The risk of graft insufficiency at 1-year follow-up was the same as in an adult population.

LEVEL OF EVIDENCE

II.

Pedi-IKDC exhibits questionable measurement properties in a cohort of pediatric patients with ACL rupture

BACKGROUND

Pedi-IKDC is commonly used to evaluate anterior cruciate ligament (ACL) deficiency in children. However, its construct validity has not been thoroughly assessed. The aim was to examine the measurement properties of the Pediatric International Knee Documentation Committee (Pedi-IKDC) by modern test theory (MTT) models, confirmatory factor analysis (CFA), and item response theory (IRT).

METHODS

The cohort consisted of all children and adolescents in Denmark (n = 535, age 9-16) treated with physeal-sparing ACL reconstruction 2011-2020. Patient-reported outcome measure (PROM) data were collected before surgery and at 1 year follow-up. Structural validity of Pedi-IKDC was assessed with MTT models. Reliability was reported as McDonalds coefficient omega. Responsiveness was evaluated with standardized response means.

RESULTS

Sufficient PROM data were available for 372 patients. The original unidimensional construct did not fit CFA model expectations neither before surgery (χ2  = 462.0, df = 163, p < 0.0001; RMSEA: 0.109, CFI: 0.910, TFI: 0.895) nor at follow-up. Neither did a two-factor CFA model with "Symptoms" and "Sports activities" as individual subscales (χ2  = 455.6, df = 162, p < 0.0001) nor a bifactor model (χ2  = 338.9, df = 143, p < 0.0001), although fit indices improved with the latter (RMSEA: 0.094, CFI: 0.941, TFI: 0.922). The IRT models confirmed this pattern. The scale was responsive (SRM 1.66 (95% CI: 1.46-1.88)). Coefficient omega values were 0.866 before surgery and 0.919 at follow-up.

CONCLUSIONS

The Pedi-IKDC exhibited inadequate structural validity. Neither the original construct, a two-factor model, nor bifactor models fitted data well. We advise that data obtained by Pedi-IKDC are interpreted with caution.

The Effect of Endoscopic Partial Plantar Fasciotomy on Morphologic and Functional Properties of the Foot

BACKGROUND

The lifetime risk of plantar fasciitis is 10%, and operative treatment in the form of endoscopic partial plantar fascia release are often performed in cases refractory for nonsurgical treatment. The effect of the operation on the biomechanical properties of the foot has only been sparsely studied.

METHODS

This is a prospective, observational study of 25 patients with plantar fasciitis, for a minimum of 3 months, verified by ultrasonographic scanning, who had endoscopic partial fasciotomy. A bony spur was resected if present. At the calcaneal insertion, the medial half of the central band of the plantar fascia was excised in full thickness. The biomechanical properties of the foot were evaluated before surgery and 12 months postoperatively.

RESULTS

Foot length increased 0.17 cm (P = .03), the width of the central zone 0.35 cm (P = .019), the modified arch index 0.05 (P = .032), and the Foot Posture Index 1.0 (P = .0014). There were no significant changes in rearfoot eversion angle, ankle dorsiflexion and jump distance, or in magnetic resonance imaging-measured 3D navicular position from pre- to postoperation, with or without loading, and no changes in ultrasonographically measured heel pad thickness. A tantalum bead (0.7-mm-diameter) was inserted during operation into the most proximal part of the released medial plantar fascia. Radiographs obtained few days postoperatively and 1 year later revealed no changes in the tantalum-calcaneus distance in supine position, but an increase from 48.3 to 50.7 mm (P = .045) in one-leg standing, suggesting a higher flexibility of the remaining fascia. Patients with a body mass index above and below 27.0 demonstrated no significant differences in any of the assessments at 12 months.

CONCLUSION

There were minimal changes in the measured foot morphologic and functional properties at 1-year follow-up, after endoscopic partial plantar fascia release.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

Hospital variation in revision rates after primary knee arthroplasty was not explained by patient selection: baseline data from 1452 patients in the Danish prospective multicenter cohort study, SPARK

PURPOSE

Revision rates following primary knee arthroplasty vary by country, region and hospital. The SPARK study was initiated to compare primary surgery across three Danish regions with consistently different revision rates. The present study investigated whether the variations were associated with differences in the primary patient selection.

METHODS

A prospective observational cohort study included patients scheduled Sep 2016 Dec 2017 for primary knee arthroplasty (total, medial/lateral unicompartmental or patellofemoral) at three high-volume hospitals, representing regions with 2-year cumulative revision rates of 1, 2 and 5%, respectively. Hospitals were compared with respects to patient demographics, preoperative patient-reported outcome measures, motivations for surgery, implant selection, radiological osteoarthritis and the regional incidence of primary surgery. Statistical tests (parametric and non-parametric) comprised all three hospitals.

RESULTS

Baseline data was provided by 1452 patients (89% of included patients, 56% of available patients). Patients in Copenhagen (Herlev-Gentofte Hospital, high-revision) were older (68.6 ± 9 years) than those in low-revision hospitals (Aarhus 66.6 ± 10 y. and Aalborg (Farsø) 67.3 ± 9 y., p = 0.002). In Aalborg, patients who had higher Body Mass Index (mean 30.2 kg/m² versus 28.2 (Aarhus) and 28.7 kg/m² (Copenhagen), p < 0.001), were more likely to be male (56% versus 45 and 43%, respectively, p = 0.002), and exhibited fewer anxiety and depression symptoms (EQ-5D-5L) (24% versus 34 and 38%, p = 0.01). The preoperative Oxford Knee Score (23.3 ± 7), UCLA Activity Scale (4.7 ± 2), range of motion (Copenhagen Knee ROM Scale) and patient motivations were comparable across hospitals but varied with implant type. Radiological classification ≥ 2 was observed in 94% (Kellgren-Lawrence) and 67% (Ahlbäck) and was more frequent in Aarhus (low-revision) (p ≤ 0.02), where unicompartmental implants were utilized most (49% versus 14 (Aalborg) and 23% (Copenhagen), p < 0.001). In the Capital Region (Copenhagen), the incidence of surgery was 15-28% higher (p < 0.001).

CONCLUSION

Patient-reported outcome measures prior to primary knee arthroplasty were comparable across hospitals with differing revision rates. While radiographic classifications and surgical incidence indicated higher thresholds for primary surgery in one low-revision hospital, most variations in patient and implant selection were contrary to well-known revision risk factors, suggesting that patient selection differences alone were unlikely to be responsible for the observed variation in revision rates across Danish hospitals.

LEVEL OF EVIDENCE

II, Prospective cohort study.

Patients in high- and low-revision hospitals have similar outcomes after primary knee arthroplasty: 1-year postoperative results from the Danish prospective multicenter cohort study, SPARK

PURPOSE

It is well-known that revision rates after primary knee arthroplasty vary widely. However, it is uncertain whether hospital revision rates are reliable indicators of general surgical quality as defined by patients. The SPARK study compared primary knee arthroplasty surgery at three high-volume hospitals whose revision rates differed for unknown reasons.

METHODS

This prospective observational study included primary knee arthroplasty patients (total, medial/lateral unicompartmental and patellofemoral) in two low-revision hospitals (Aarhus University Hospital and Aalborg University Hospital Farsø) and one high-revision hospital (Copenhagen University Hospital Herlev-Gentofte). Patients were followed from preoperatively (2016-17) to 1-year postoperatively with patient-reported outcome measures including Oxford Knee Score (OKS), EQ-5D-5L and Copenhagen Knee ROM (range of motion) Scale. The surgical outcomes were compared across hospitals for patients with comparable grades of radiographic knee osteoarthritis and preoperative OKS. Statistical comparisons (parametric and non-parametric) included all three hospitals.

RESULTS

97% of the 1452 patients who provided baseline data (89% of those included and 56% of those operated) responded postoperatively (90% at 1 year). Hospitals' utilization of unicompartmental knee arthroplasties differed (Aarhus 49%, Aalborg 14%, and Copenhagen 22%, p < 0.001). 28 patients had revision surgery during the first year (hospital independent, p = 0.1) and were subsequently excluded. 1-year OKS (39 ± 7) was independent of hospital (p = 0.1), even when adjusted for age, sex, Body Mass Index, baseline OKS and osteoarthritis grading. 15% of patients improved less than Minimal Important Change (8 OKS) (Aarhus 19%, Aalborg 13% and Copenhagen 14%, p = 0.051 unadjusted). Patients with comparable preoperative OKS or osteoarthritis grading had similar 1-year results across hospitals (OKS and willingness to repeat surgery, p ≥ 0.087) except for the 64 patients with Kellgren-Lawrence grade-4 (Aarhus 4-6 OKS points lower). 86% of patients were satisfied, and 92% were "willing to repeat surgery", independent of hospital (p ≥ 0.1). Hospital revision rates differences diminished during the study period.

CONCLUSIONS

Patients in hospitals with a history of differing revision rates had comparable patient-reported outcomes 1 year after primary knee arthroplasty, supporting that surgical quality should not be evaluated by revision rates alone. Future studies should explore if revision rate variations may depend as much on revision thresholds and indications as on outcomes of primary surgery.

LEVEL OF EVIDENCE

Level II (Prospective cohort study).

Evaluation of hop performance in children with anterior cruciate ligament reconstruction using healthy reference data: A cross-sectional study

BACKGROUND

Hop performance evaluation in children after anterior cruciate ligament (ACL) reconstruction may benefit from comparison to healthy controls. Thus, the purpose was to investigate the hop performance in children one year after ACL reconstruction with a comparison to healthy controls.

METHODS

Hop performance data from children with ACL reconstruction one year post-surgery and healthy children were compared. Four one-legged hop test data were analyzed: 1) single hop (SH), 2) 6 m timed hop (6 m-timed), 3) triple hop (TH), and 4) cross-over hop (COH). Outcomes were the best result (longest/fastest hop) from each leg and limb asymmetry. Differences in hop performance between-limbs (operated versus non-operated) and between-groups were estimated.

RESULTS

98 children with ACL reconstruction and 290 healthy children were included. Few statistically significant group differences were observed. Girls with ACL reconstruction outperformed healthy controls in two tests on the operated leg SH, COH) and in three tests on the non-operated leg (SH, TH, COH). However, the girls performed 4-5% worse on the operated leg when compared to the non-operated leg in all hop tests. No statistically significant between-group differences in the limb asymmetry were found.

CONCLUSION

The hop performance in children with ACL reconstruction one year post-surgery was largely comparable to the level of healthy controls. Despite this, we cannot exclude that neuromuscular deficits exist among the children with ACL reconstruction. The inclusion of a healthy control group for evaluating hop performance evoked complex findings regarding the ACL reconstructed girls. Thus, they may represent a selected group.

Larger interface area at the human myotendinous junction in type 1 compared with type 2 muscle fibers

The myotendinous junction (MTJ) is structurally specialized to transmit force. The highly folded muscle membrane at the MTJ increases the contact area between muscle and tendon and potentially the load tolerance of the MTJ. Muscles with a high content of type II fibers are more often subject to strain injury compared with muscles with type I fibers. It is hypothesized that this is explained by a smaller interface area of MTJ in type II compared with type I muscle fibers. The aim was to investigate by confocal microscopy whether there is difference in the surface area at the MTJ between type I and II muscle fibers. Individual muscle fibers with an intact MTJ were isolated by microscopic dissection in samples from human semitendinosus, and they were labeled with antibodies against collagen XXII (indicating MTJ) and type I myosin (MHCI). Using a spinning disc confocal microscope, the MTJ from each fiber was scanned and subsequently reconstructed to a 3D-model. The interface area between muscle and tendon was calculated in type I and II fibers from these reconstructions. The MTJ was analyzed in 314 muscle fibers. Type I muscle fibers had a 22% larger MTJ interface area compared with type II fibers (p < 0.05), also when the area was normalized to fiber diameter. By the new method, it was possible to analyze the structure of the MTJ from a large number of human muscle fibers. The finding that the interface area between muscle and tendon is higher in type I compared with type II fibers suggests that type II fibers are less resistant to strain and therefore more susceptible to injury.

Four of five frequently used orthopedic PROMs possess inadequate content validity: a COSMIN evaluation of the mHHS, HAGOS, IKDC-SKF, KOOS and KNEES-ACL

PURPOSE

Content validity is the most important property of PROMs. The COSMIN initiative has published guidelines for evaluating the content validity of PROMs, but they have only sparsely been applied to relevant PROMs for musculoskeletal conditions. The aim of this study was to use the COSMIN Risk of Bias checklist to evaluate the content validity of five PROMs, that are highly relevant in musculoskeletal research and used by the arthroscopic surgery community: the modified Harris' Hip Score (mHHS), the Copenhagen Hip and Groin Outcome Score (HAGOS), the International Knee Documentation Committee Subjective Knee evaluation Form (IKDC-SKF), the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Knee Numeric-Entity Evaluation Score ACL (KNEES-ACL).

METHODS

The development articles for the five PROMs were identified through searches in PubMed and SCOPUS. A literature search was performed to identify additional studies assessing content validity of the PROMs. Additional information, necessary for the assessments, was obtained from the PROM developers after direct request. To evaluate the quality of the development studies and rate the content validity, the COSMIN Risk of Bias checklist was applied to all studies.

RESULTS

All five development studies were identified. Three subsequent content validity studies were identified, all evaluating KOOS and one also IKDC. One content validity study was of inadequate quality and excluded from further analysis. The development of mHHS, IKDC-SKF, and KOOS was rated inadequate and possess insufficient content validity for their target populations. Due to the irrelevance of multiple items, KOOS was in particular inappropriate to evaluate patients with an ACL injury. The development of HAGOS was also rated inadequate, although the insufficiency aspects can be regarded as minor. KNEES-ACL possessed sufficient content validity.

CONCLUSION

Out of five PROMs, only KNEES-ACL possessed sufficient content validity. Particularly, KOOS should not be used as an outcome for patients with an ACL injury. There is an urgent need for condition-specific PROMs for musculoskeletal conditions, developed with adequate methods.

LEVEL OF EVIDENCE

III.

Acetabular retroversion does not affect outcome in primary hip arthroscopy for femoroacetabular impingement

PURPOSE

The surgical treatment of femoral-acetabular impingement syndrome (FAIS) in patients with acetabular retroversion (AR) is arthroscopical or by a reverse periacetabular osteotomy (PAO). The purpose of the present study was to investigate the results after arthroscopic treatment of FAIS in patients with and without radiographic signs of AR in a large, prospective cohort from the Danish Hip Arthroscopy Registry (DHAR). The hypothesis was there is no difference in clinical outcome between the two groups.

METHODS

Data on 4914 hip arthroscopies performed during 2012-2019 were obtained from DHAR. Patients with radiographic signs of osteoarthritis (Tönnis > 1), hip dysplasia (CEA < 25°), other hip pathologies or previous hip surgery were excluded. The clinical outcomes for patients with AR [defined by a positive posterior wall sign (PWS) in combination with a positive Ischial Spine Sign (ISS)] and patients without AR (no PWS, no ISS) were analyzed 1 and 2 years after surgery. The primary outcomes were the six domains of the Copenhagen Hip and Groin Outcome score (HAGOS), while secondary outcomes were the Hip Sports Activity Scale (HSAS), a visual analogue pain scale (VAS) and a numeric rating scale (NRS) for pain.

RESULTS

A total of 3135 hip arthroscopies were included, of which 339 had AR, 1876 did not, and 920 presented one of the two signs (PWS and ISS). There were no statistically significant differences 1 and 2 years after surgery (n.s.) between patients with and without AR in HAGOS domain scores, HSAS, VAS, or NRS. Both groups showed improvement at both follow-ups. The two groups did not differ in relation to intraoperative findings and the procedures they have had.

CONCLUSION

The outcome 1 and 2 years after arthroscopic treatment of FAIS is not different for patients with and without AR.

LEVEL OF EVIDENCE

III.

No correlation between performance tests, clinical measurements and data from patient-reported outcome measures (PROM) in children reconstructed for anterior cruciate ligament injury

PURPOSE

To investigate if patient-reported outcome measures (PROMs), functional tests and clinical measures correlate well in children after reconstruction of the anterior cruciate ligament (ACL). It was hypothesized that these outcomes correlate, so it is sufficient to report only one of them.

METHODS

A consecutive group of children (< 16 years old) who had an ACL reconstruction, were prospectively followed and assessed after 1-year with Pedi-IKDC and KOOS-Child, instrumented laxity measurement, range of motion, extension strength and four performance tests. Relations between the different outcomes were calculated by partial correlation coefficient analysis, controlling for gender, age, height, and weight.

RESULTS

Outcomes were available for 141 of 163 children. There were only few positive and weak correlations between performance tests and PROM scores and between clinical measurements and PROM scores. There were weak to strong correlations between the scores from Pedi-IKDC and the scores from each of the five domains of KOOS-Child and a weak to moderate correlation between the different domains of KOOS-Child. Similar correlations were found between the different performance tests.

CONCLUSION

For children who had their ACL reconstructed there was no clinically important correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. This is an argument for always to include and report all three types of outcomes.

LEVEL OF EVIDENCE

Level II.

Dual-panel translation to Danish and Rasch validation of the Foot and Ankle Ability Measure (FAAM-DK)

BACKGROUND

The Foot and Ankle Ability Measure (FAAM) was developed by involvement of patients with chronic ankle instability (CAI) and has acceptable measurement properties, but is not available in Danish.

METHODS

FAAM was translated and culturally adapted into Danish, and its measurement properties were assessed using Rasch analyses.

RESULTS

A Danish version was produced with small adaptations, and content relevance was confirmed by Danish patients. The 21-item ADL domain showed misfit to the Rasch model, but after removing six items, the resulting 15-item scale displayed adequate fit. The Sports domain also exhibited misfit, but after removing one item and adjusting due to differential item functioning related to age for another item, a 7-item scale showed good fit. This resulted in a 22-item 2-dimensional Danish version of FAAM.

CONCLUSION

The 22-item Danish FAAM exhibits robust measurement properties for patients with various conditions of the lower leg, ankle, and foot, including CAI.

The Myotendinous Junction-A Vulnerable Companion in Sports. A Narrative Review

The incidence of strain injuries continues to be high in many popular sports, especially hamstring strain injuries in football, despite a documented important effect of eccentric exercise to prevent strains. Studies investigating the anatomical properties of these injuries in humans are sparse. The majority of strains are seen at the interface between muscle fibers and tendon: the myotendinous junction (MTJ). It has a unique morphology with a highly folded muscle membrane filled with invaginations of collagen fibrils from the tendon, establishing an increased area of force transmission between muscle and tendon. There is a very high rate of remodeling of the muscle cells approaching the MTJ, but little is known about how the tissue adapts to exercise and which structural changes heavy eccentric exercise may introduce. This review summarizes the current knowledge about the anatomy, composition and adaptability of the MTJ, and discusses reasons why strain injuries can be prevented by eccentric exercise.

Effects of 12 Weeks of Progressive Early Active Exercise Therapy After Surgical Rotator Cuff Repair: 12 Weeks and 1-Year Results From the CUT-N-MOVE Randomized Controlled Trial

BACKGROUND

Traumatic full-thickness rotator cuff tears are typically managed surgically, followed by rehabilitation, but the load progression to reach an optimal clinical outcome during postoperative rehabilitation is unknown.

PURPOSE

To evaluate whether there was a superior effect of 12 weeks of progressive active exercise therapy on shoulder function, pain, and quality of life compared with usual care.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients with surgically repaired traumatic full-thickness rotator cuff tears were recruited from 2 orthopaedic departments and randomized to progressive active exercise therapy (PR) or limited passive exercise therapy (UC [usual care]). The primary outcome was the change in the Western Ontario Rotator Cuff Index (WORC) score between groups from before surgery to 12 weeks after surgery. Secondary outcomes included changes in the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire score, pain, range of motion, and strength. Adverse events were registered during the intervention period.

RESULTS

A total of 82 patients were randomized to the PR (n = 41) or UC (n = 41) group. All 82 patients (100%) participated in the 12-week assessment and 79 in the 1-year follow-up. At 12 weeks, there was no significant difference between the groups in the change in the WORC score from baseline adjusted for age, sex, and center (physical symptoms: P = .834; sports and recreation: P = .723; work: P = .541; lifestyle: P = .508; emotions: P = .568). Additionally, there was no between-group difference for the secondary outcomes including the WORC score at 1 year and the DASH score, pain, range of motion, and strength at 12 weeks and 1 year. Both groups showed significant improvements over time in all outcomes. In total, there were 13 retears (16%) at 1-year follow-up: 6 in the PR group and 7 in the UC group.

CONCLUSION

PR did not result in superior patient-reported and objective outcomes compared with UC at either short- or long-term follow-up (12 weeks and 1 year).

REGISTRATION

NCT02969135 (ClinicalTrials.gov identifier).

Are PROMs used adequately in sports research? An analysis of 54 randomized controlled trials with PROMs as endpoint

Deviations from adequate use and reporting of PROMs may be problematic and misleading. The aim of this study was to investigate the extent of such problems in randomized clinical trials (RCTs). RCTs involving sports medicine research that used PROMs as primary outcomes were identified in 13 preselected journals. The articles were reviewed for nine potential problems related to how the PROM was used and how the data had been reported. The potential problems were as follows: aggregating subscale scores; combining patient-reported scores with physical, clinical, or para-clinical measures; using a PROM to diagnose or evaluate the individual patient; using a PROM for one leg or arm; selectively excluding domains or items; constructing a PROM for the specific occasion; mixing PROM formats (ie, digital, paper, telephone, e-mail, in person); ambiguous instructions for how the PROM should be completed; and recall bias. As covariates, we registered journal impact factor, year of publication, and existence of a registered protocol. In 29 (53.7%) of 54 identified RCTs, at least one potential problem was identified, the most common being aggregation of domain scores. This was not different with a published protocol or dependent on journal rankings, except for exclusion of domains, which was most common in high-ranking journals. Aggregation of domain scores was significantly less common in recently published articles compared with older articles (P = .03). Potential problematic use of PROMs and reporting of PROM data are common in RCTs, also in high-ranking journals, but less so in more recent articles.

Gracilis tendon harvest may lead to both incisional and non-incisional saphenous nerve injuries

PURPOSE

The purpose of this study was to map saphenous nerve injuries after gracilis tendon harvest, with the aim of contributing knowledge that makes it possible to prevent these injuries.

METHODS

Twenty-two cadaver limbs were used. Three were dissected to examine fascial structures between the saphenous nerve and the gracilis tendon. In 19 limbs, the gracilis tendon was harvested according to standard operative routine. The saphenous nerve was subsequently exposed by dissection and injuries were recorded.

RESULTS

A well-defined sub-sartorial fascial layer separated the saphenous nerve from the gracilis tendon. Incisional injuries involving either a medial cutaneous crural branch or the infrapatellar branch were found in 14 of the 19 cases. Non-incisional injuries affecting the sartorial branch of the saphenous nerve (to conform to most surgical literature, we use the term 'sartorial branch' to denote the continuation of the saphenous nerve after departure of the infrapatellar branch) were found in six cases located 5-8 cm proximal and posterior to the gracilis tendon insertion on tibia. The fascia separating the saphenous nerve from the gracilis tendon had been perforated in relation to all non-incisional injuries.

CONCLUSIONS

Small subcutaneous branches of the saphenous nerve are at risk of injury from the incision, while the sartorial branch is at risk outside the incision area. Descriptions of the location of non-incisional injuries have not been published before and are of clinical relevance, as they can contribute to the prevention of saphenous nerve injuries during gracilis tendon harvest.

Complications and technical failures are rare in knee ligament reconstruction: analyses based on 31,326 reconstructions during 10 years in Denmark

PURPOSE

Knowledge about treatment injuries (technical failures and complications) in relation to knee ligament reconstructions is sparse. Our purpose was to describe treatment injuries to knee ligament reconstruction in Denmark during a 10-year period and to suggest initiatives to reduce the risk for treatment injuries.

METHODS

Treatment injuries after knee ligament reconstructions reported to the Danish Patient Compensation Association (DPCA) 2005-2014 were analyzed and compared to information from the Danish Kneeligament Reconstruction Register and Danish National Patient Register.

RESULTS

The number of knee ligament reconstructions in Denmark 2005-2014, including revisions, was 31,326. Of the 704 cases claimed to DPCA, 371 were approved as treatment injuries (1.42% of all operations). Tunnel malpositioning (135 = 0.43% of all operations), deep infection (0.27%), nerve injury (0.17%), pain (0.12%) and unrecognized combined instability (0.11%) were the most common. Patients operated with anteromedial technique for femoral tunnel placement had a lower incidence (p < 0.0001) of tunnel malpositioning compared to other techniques. Public and private hospitals had the same risk of treatment injures. Hospitals that performed the largest number of reconstructions/year had the smallest risk of a treatment injury (p < 0.001). The total compensation was 7.6 m EURO, which equals 243 EURO/performed knee ligament reconstruction.

CONCLUSION

Treatment injuries as defined in this study were rare, with tunnel malpositioning being the most common. Analyses of the results indicate that it may be clinically relevant to reduce the number of treatment injures that knee ligament reconstructions are concentrated in clinics with high volume. Also, malpositioning might be reduced by routine documentation of K-wire position before tunnels are drilled.

LEVEL OF EVIDENCE

III.

Plantar fasciitis treated with endoscopic partial plantar fasciotomy-One-year clinical and ultrasonographic follow-up

BACKGROUND

Endoscopic operations for plantar fasciitis generally have good clinical outcome. The aim of this study was to record the effect of endoscopic partial fasciotomy and heel spur removal and evaluate by ultrasonography whether the fascia regenerates and the heel spur reforms.

METHODS

Eleven consecutive patients were evaluated before and 3, 6 and 12 months after surgery. Operations were performed endoscopically using a deep fascial approach with a medial and a lateral portal. Bony spurs were removed and the medial half of the plantar fascia was transected. All patients followed a standardized rehabilitation program.

RESULTS

Median Foot Function Index values decreased from 119 pre-surgery to 69 and 12 (p=0.004), at 3 months and 1year post-operatively respectively. Median VAS-score for first step pain was likewise reduced from median 71mm to 29mm and 7mm (p=0.004), respectively. Median fascial thickness at the medial insertion was 6.0mm (range 4.6-6.8mm) pre-operatively. A heel spur was present in 9 cases. One year postoperatively a well-defined fascia in the area of resection was demonstrated in 8 cases. In the rest of the cases scar tissue made it impossible to clearly outline the fascia. Nine of the feet showed good medial fascial tensioning. There was no evidence of recurrence of the bony spur.

CONCLUSIONS

Endoscopic partial plantar fascia resection reduced pain symptoms and increased function significantly 3 months after operation, with additional effect achieved 12 months after surgery. Based on ultrasonography the resected fascia regenerated/healed, and a calcaneal spur did not recur.

[Scapula - friend and foe]

A well-functioning scapula provides a stable base for the humerus and allows free motion of the arm through a smooth glide over the posterior thoracic wall. This is possible through intimate interaction between anatomy and muscles. This can be disturbed by painful conditions, nerve dysfunctions, over-/underperformance of muscles, anatomic variations and trauma. In this review, we describe anatomy, biomechanics and different pathologies of the scapula: muscular imbalances, nerve dysfunctions, snapping scapula, tumours and fractures. We discuss, how the different conditions are diagnosed and treated.

[Sternoclavicular joint disorders]

In this review, function, anatomy and pathology of the sternoclavicular joint is described. Arthritis as part of a rheumatological condition is treated medically; persistent synovitis can be treated by synovectomy. Infection is most often caused by Staphylococcus and is treated by debridement and antibiotics. Painful degenerative conditions can be treated by arthroscopic or open debridement, medial clavicle resection and resection of osteophytes. Instability can be traumatic or non-traumatic and is treated by a stabilising operation. Generally, results of treatment are positive.

Progressive early passive and active exercise therapy after surgical rotator cuff repair - study protocol for a randomized controlled trial (the CUT-N-MOVE trial)

Background

Rotator cuff tear is a common cause of shoulder disability and results in patients predominantly complaining of pain and loss of motion and strength. Traumatic rotator cuff tears are typically managed surgically followed by ~ 20 weeks of rehabilitation. However, the timing and intensity of the postoperative rehabilitation strategy required to reach an optimal clinical outcome is unknown. Early controlled and gradually increased tendon loading has been suggested to positively influence tendon healing and recovery. The aim of this trial is therefore to examine the effect of a progressive rehabilitation strategy on pain, physical function and quality of life compared to usual care (that limits tendon loading in the early postoperative phase) in patients who have a rotator cuff repair of a traumatic tear.

Methods

The current study is a randomized, controlled, outcome-assessor blinded, multicenter, superiority trial with a two-group paralleled design. A total of 100 patients with surgically repaired traumatic rotator cuff tears will be recruited from up to three orthopedic departments in Denmark, and randomized to either a progressive early passive and active movement program or a limited early passive movement program (usual care). The primary outcome measure will be the change from pre-surgery to 12 weeks post-surgery in the Western Ontario Rotator Cuff Index questionnaire. Secondary outcomes include the Disabilities Arm, Shoulder and Hand questionnaire (DASH), range of motion, strength and tendon healing characteristics from ultrasound measurements at 12 months follow up.

Discussion

We hypothesized that patients who receive the progressive rehabilitation strategy will benefit more with respect to pain reduction, physical function and quality of life than those who receive care as usual. If this is confirmed our study can be used clinically to enhance the recovery of patients with traumatic rotator cuff tear.

Trial registration

ClinicalTrials.gov, NCT02969135. Registered on 15 November 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2839-5) contains supplementary material, which is available to authorized users.

Why tibial plateau fractures are overlooked

BACKGROUND

Tibial plateau fractures (TPFs) are sometimes overlooked in the emergency room (ER). Using a national register covering 18 years we aimed to find out why and to evaluate if use of a specific radiographic decision rule, Pittsburgh Knee Rules (PKRs), could have reduced the number of overlooked TPFs.

METHODS

Medical records for 137 patients, prospectively registered during 18 years by the Danish Patient Compensation Association (DPCA) (a national register), were studied. The inclusion criterion was a delayed diagnosis of a fracture in the knee following a trauma. Case records, legal assessments, and evaluations by specialist doctors were reviewed, and the consequences of the delayed diagnosis for outcome and treatment were registered.

RESULTS

Only 58 patients (42%) had been evaluated according to PKRs. In 53 patient cases, the fracture was not diagnosed on radiographs obtained at the first medical contact. However, in 84% of these cases, the fracture was visible or was suspected by retrospective evaluation. 50 out of 79 patients, for whom X-rays were not obtained, were candidates for radiographs according to PKRs, 17 cases lacked information to evaluate by PKRs and 12 cases were not candidates. In 53% of all cases, it was evaluated that the fracture position had worsened at the time of diagnosis. A significant disability compensation was granted in 36% of cases due to the delayed identification of fractures, totaling 841,000 EUR.

CONCLUSIONS

The major reasons for overlooking TPFs were 1) difficulty in recognizing the fractures on X-rays and 2) that X-ray decision rules were not employed. Two thirds of the patients, for whom a radiograph had not been prescribed, would have had an X-ray, if the PKRs had been used. Overlooking TPFs significantly increased patient disability in one third of cases. We recommend that healthcare professionals in the ER use X-ray decision rules in addition to clinical examination to avoid overlooking TPFs. When standard radiographs are evaluated as normal in patients that are clinically suspect of a TPF, oblique X-rays, magnetic resonance imaging (MRI) or Computed Tomography (CT)-scan should be considered.

Remodeling of muscle fibers approaching the human myotendinous junction

The myotendinous junction (MTJ) is at high risk of strain injuries, due to high amounts of energy that is transferred through this structure. The risk of strain injury is significantly reduced by heavy resistance training (HRT), indicating a remodeling capacity of MTJ. We investigated the degree of remodeling of muscle fibers near the human MTJ. In 8 individuals, samples were taken from the semitendinosus and gracilis MTJ and they were stained immunohistochemically for myonuclei (DAPI), fibroblasts (TCF7L2), and satellite cells (CD56). A high portion of the muscle fibers adjacent to the MTJ contained a centrally located myonucleus (47 ± 8%, mean ± SD) and half of the muscle fibers were CD56 positive. The number of satellite cells and fibroblasts were not higher than what has previously been reported from muscle bellies. The immunohistochemical findings suggest that the rate of remodeling of muscle fibers near the MTJ is very high. The finding that there was no increased number of satellite cells and fibroblasts could be explained as a dynamic phenomenon. The effect of HRT should be evaluated in a randomized setting.

Snapping elbow-A guide to diagnosis and treatment

AIM

To develop practical guidelines for diagnosis and treatment of the painful snapping elbow syndrome (SE).

METHODS

Clinical studies were searched in the databases PubMed and Scopus for the phrases “SE”, “snapping triceps”, “snapping ulnar nerve” and “snapping annular ligament”. A total of 36 relevant studies were identified. From these we extracted information about number of patients, diagnostic methods, patho-anatomical findings, treatments and outcomes. Practical guidelines for diagnosis and treatment of SE were developed based on analysis of the data. We present two illustrative patient cases-one with intra-articular pathology and one with extra-articular pathology.

RESULTS

Snapping is audible, palpable and often visible. It has a lateral (intra-articular) or medial (extra-articular) pathology. Snapping over the medial humeral epicondyle is caused by dislocation of the ulnar nerve or a part of the triceps tendon, and is demonstrated by dynamic ultrasonography. Treatment is by open surgery. Lateral snapping over the radial head has an intra-articular pathology: A synovial plica, a torn annular ligament or a meniscus-like remnant from the foetal elbow. Pathology can be visualized by conventional arthrography, magnetic resonance (MR) arthrography, high resolution magnetic resonance imaging (MRI) and arthroscopy, while conventional MRI and radiographs often turn out normal. Treatment is by arthroscopic or eventual open resection. Early surgical intervention is recommended as the snapping can damage the ulnar nerve (medial) or the intra-articular cartilage (lateral). If medial snapping only occurs during repeated or loaded extension/flexion of the elbow (in sports or work) it may be treated by reduction of these activities. Differential diagnoses are loose bodies (which can be visualized by radiographs) and postero-lateral instability (demonstrates by clinical examination). An algorithm for diagnosis and treatment is suggested.

CONCLUSION

The primary step is establishment of laterality. From this follows relevant diagnostic measures and treatment as defined in this guideline.

Well Leg Compartment Syndrome After Abdominal Surgery

BACKGROUND

Well leg compartment syndrome (WLCS) is a complication to abdominal surgery. We aimed to identify risk factors for and outcome of WLCS in Denmark and literature.

METHODS

Prospectively collected claims to the Danish Patient Compensation Association (DPCA) concerning WLCS after abdominal operations 1996-2013 and cases in literature 1970-2013 were evaluated. Cases of fasciotomy within 2 weeks after abdominal surgery 1999-2008 were extracted from the Danish National Patient Register (DNPR).

RESULTS

There were 40 cases in DPCA and 124 in literature. In 68 % legs were supported under the knees during surgery. Symptoms of WLCS presented within 2 h after surgery in 56 % and in only 3 cases after 24 h. Obesity was not confirmed as risk factor for WLCS. The mean diagnostic delay was 10 h. One-third of fasciotomies were insufficient. The diagnostic delay increased with duration of the abdominal surgery (p = 0.04). Duration of the abdominal surgery was 4 times as important as the diagnostic delay for severity of the final outcome. DNPR recorded 4 new cases/year, and half were reported to DPCA.

CONCLUSION

The first 24 h following abdominal surgery of >4 h' duration with elevated legs observation for WLCS should be standard. Pain in the calf is indicative of WLCS, and elevated serum CK can support the diagnosis. Mannitol infusion and acute four-compartment fasciotomy of the lower leg is the treatment. The risk of severe outcome of WLCS increases with duration of the primary operation. A broad support and change of legs' position during surgery are suggested preventative initiatives.

Possibilities for arthroscopic treatment of the ageing sternoclavicular joint

AIM

To investigate if there are typical degenerative changes in the ageing sternoclavicular joint (SCJ), potentially accessible for arthroscopic intervention.

METHODS

Both SCJs were obtained from 39 human cadavers (mean age: 79 years, range: 59-96, 13 F/26 M). Each frozen specimen was divided frontally with a band saw, so that both SCJs were opened in the same section through the center of the discs. After thawing of the specimens, the condition of the discs was evaluated by probing and visual inspection. The articular cartilages were graded according to Outerbridge, and disc attachments were probed. Cranio-caudal heights of the joint cartilages were measured. Superior motion of the clavicle with inferior movement of the lateral clavicle was measured.

RESULTS

Degenerative changes of the discs were common. Only 22 discs (28%) were fully attached and the discs were thickest superiorly. We found a typical pattern: Detachment of the disc inferiorly in connection with thinning, fraying and fragmentation of the inferior part of the disc, and detachment from the anterior and/or posterior capsule. Severe joint cartilage degeneration ≥ grade 3 was more common on the clavicular side (73%) than on the sternal side (54%) of the joint. In cadavers < 70 years 75% had ≤ grade 2 changes while this was the case for only 19% aged 90 years or more. There was no difference in cartilage changes when right and left sides were compared, and no difference between sexes. Only one cadaver - a woman aged 60 years - had normal cartilages.

CONCLUSION

Changes in the disc and cartilages can be treated by resection of disc, cartilage, intraarticular osteophytes or medial clavicle end. Reattachment of a degenerated disc is not possible.

Composition and adaptation of human myotendinous junction and neighboring muscle fibers to heavy resistance training

The myotendinous junction (MTJ) is a common site of strain injury and yet understanding of its composition and ability to adapt to loading is poor. The main aims of this study were to determine the profile of selected collagens and macrophage density in human MTJ and adjoining muscle fibers, and to investigate whether heavy exercise loading would alter this profile. Fifteen individuals scheduled for anterior cruciate ligament repair surgery were randomized into three groups: control, acute or 4 weeks heavy resistance training. MTJ samples were collected from the semitendinosus and gracilis muscles and were sectioned and stained immunohistochemically for collagen types I, III, VI, XII, XIV, XXII, Tenascin-C and CD68. Macrophage density and distribution was evaluated and the amount of each collagen type in muscle and MTJ was graded. Collagen XXII was observed solely at the MTJ, while all other collagens were abundant at the MTJ and in muscle perimysium or endomysium. The endomysial content of collagen XIV, macrophages and Tenascin-C increased following 4 weeks of training. These findings illustrate the heterogeneity of collagen type composition of human MTJ. The increase in collagen XIV following 4 weeks of training may reflect a training-induced protection against strain injuries in this region.

The role of the anterolateral ligament in ACL insufficient and reconstructed knees on rotatory stability: A biomechanical study on human cadavers

Studies suggest that the anterolateral ligament (ALL) is important for knee stability. The purpose was to clarify ALL's effect on rotatory and anterior-posterior stability in the anterior cruciate ligament (ACL)-insufficient and reconstructed knees and the effect of reconstruction of an insufficient ALL. Eighteen cadaveric knees were included. Stability was tested for intact (+ALL), detached (-ALL) and reconstructed (+ reALL) ALL, with ACL removed (-ACL) and reconstructed (+ACL) in six combinations. All were tested in 0, 30, 60, and 90 °C flexion. Anterior-posterior stability was measured with a rolimeter. Rotation with a torque of 8.85 Nm was measured photographically. The ALL was well defined in 78% of knees. ACL reconstruction had a significant effect on anterior-posterior stability. Detaching the ALL had a significant effect on internal rotatory stability and on anterior-posterior stability in ACL-insufficient knees. Reconstruction of ACL and ALL reestablished knee stability. The appearance of the ALL was not uniform. The ALL was an internal rotational stabilizer. Anatomical ALL reconstruction in combination with ACL reconstruction could reestablish stability. ALL reconstruction might be considered in patients with combined ACL and ALL tears, but the clinical effect should be established in a controlled clinical study.

The human myotendinous junction: an ultrastructural and 3D analysis study

The myotendinous junction (MTJ) is a specialized structure in the musculotendinous system, where force is transmitted from muscle to tendon. Animal models have shown that the MTJ takes form of tendon finger-like processes merging with muscle tissue. The human MTJ is largely unknown and has never been described in three dimensions (3D). The aim of this study was to describe the ultrastructure of the human MTJ and render 3D reconstructions. Fourteen subjects (age 25 ± 3 years) with isolated injury of the anterior cruciate ligament (ACL), scheduled for reconstruction with a semitendinosus/gracilis graft were included. Semitendinosus and gracilis tendons were stripped as grafts for the ACL reconstruction. The MTJ was isolated from the grafts and prepared for transmission electron microscopy (TEM) and focused ion beam/scanning electron microscopy. It was possible to isolate recognizable MTJ tissue from all 14 patients. TEM images displayed similarities to observations in animals: Sarcolemmal evaginations observed as finger-like processes from the tendon and endomysium surrounding the muscle fibers, with myofilaments extending from the final Z-line of the muscle fiber merging with the tendon tissue. The 3D reconstruction revealed that tendon made ridge-like protrusions, which interdigitiated with groove-like indentations in the muscle cell.

Dimensionality of the Knee Numeric-Entity Evaluation Score (KNEES-ACL): a condition-specific questionnaire

The benefit of anterior cruciate ligament (ACL) reconstruction has been questioned based on patient-reported outcome measures (PROMs). Valid interpretation of such results requires confirmation of the psychometric properties of the PROM. Rasch analysis is the gold standard for validation of PROMs, yet PROMs used for ACL reconstruction have not been validated using Rasch analysis. We used Rasch analysis to investigate the psychometric properties of the Knee Numeric-Entity Evaluation Score (KNEES-ACL), a newly developed PROM for patients treated for ACL deficiency. Two-hundred forty-two patients pre- and post-ACL reconstruction completed the pilot PROM. Rasch models were used to assess the psychometric properties (e.g., unidimensionality, local response dependency, and differential item functioning). Forty-one items distributed across seven unidimensional constructs measuring impairment, functional limitations, and psychosocial consequences were confirmed to fit Rasch models. Fourteen items were removed because of statistical lack of fit and inadequate face validity. Local response dependency and differential item functioning were identified and adjusted. The KNEES-ACL is the first Rasch-validated condition-specific PROM constructed for patients with ACL deficiency and patients with ACL reconstruction. Thus, this instrument can be used for within- and between-group comparisons.

Ultrasound-guided continuous suprascapular nerve block for adhesive capsulitis: one case and a short topical review

We present a case with an ultrasound-guided (USG) placement of a perineural catheter beneath the transverse scapular ligament in the scapular notch to provide a continuous block of the suprascapular nerve (SSN). The patient suffered from a severe and very painful adhesive capsulitis of the left shoulder secondary to an operation in the same shoulder conducted 20 weeks previously for impingement syndrome and a superior labral anterior-posterior tear. Following a new operation with capsular release, the placement of a continuous nerve block catheter subsequently allowed for nearly pain-free low impact passive and guided active mobilization by the performing physiotherapist for three consecutive weeks. This case and a short topical review on the use of SSN block in painful shoulder conditions highlight the possibility of a USG continuous nerve block of the SSN as sufficient pain management in the immediate post-operative period following capsular release of the shoulder. Findings in other painful shoulder conditions and suggestions for future studies are discussed in the text.

Early osteoarthritis and microdialysis: a novel in vivo approach for measurements of biochemical markers in the perisynovium and intraarticularly

The microdialysis technique was evaluated as a possible method to obtain local measurements of biochemical markers from knee joints with degenerative changes. Seven patients scheduled for arthroscopy of the knee due to minor to moderate degenerative changes had microdialysis catheters inserted under ultrasonographic guidance, intraarticularly and in the synovium-close tissue. Catheters were perfused at a rate of 2 μl/min for approximately 100 min with a Ringer solution containing radioactively labeled glucose, and the positions of the catheters were later visualized during arthroscopy. All intraarticular catheters and 6/7 subsynovial catheters were positioned correctly. Relative recovery (RR) was intraarticularly 0.64 ± 0.02 (mean ± SEM) and synovium-close 0.54 ± 0.06. Mean values of cartilage oligomeric matrix protein (COMP), aggrecan and glucosyl-galactosyl-pyridinoline in the intraarticular dialysates were 18.1 ± 7.0 U/l, 243.6 ± 108.6 ng/ml and 108.0 ± 29.0 pmol/ml, respectively. COMP and glucosyl-galactosyl-pyridinoline concentrations were significantly higher intraarticularly compared to perisynovial tissue (P < 0.05), whereas for aggrecan, no significant difference was found (P = 0.06). The microdialysis method can be used for intraarticular and subsynovial determination of metabolites in human knees at these sites. The present methodology displays a potential for future studies of simultaneous biochemical changes within and around joints.

From mechanical loading to collagen synthesis, structural changes and function in human tendon

The adaptive response of connective tissue to loading requires increased synthesis and turnover of matrix proteins, with special emphasis on collagen. Collagen formation and degradation in the tendon increases with both acute and chronic loading, and data suggest that a gender difference exists, in that females respond less than males with regard to an increase in collagen formation after exercise. It is suggested that estrogen may contribute toward a diminished collagen synthesis response in females. Conversely, the stimulation of collagen synthesis by other growth factors can be shown in both animal and human models where insulin-like growth factor 1 (IGF-I) and transforming growth factor-beta-1 (TGF-beta-1) expression increases to accompany or precede an increase in procollagen expression and collagen synthesis. In humans, it can be demonstrated that an increase in the interstitial concentration of TGF-beta, PGE2, IGF-I plus its binding proteins and interleukin-6 takes place after exercise. The increase in IGF-I expression in tendon includes the isoform that has so far been thought only to exist in skeletal muscle (mechano growth factor). The increase in IGF-I and procollagen expression showed a similar response whether the tendon was stimulated by concentric, isometric or eccentric muscle contraction, suggesting that strain rather that stress/torque determines the collagen-synthesis stimulating response seen with exercise. The adaptation time to chronic loading is longer in tendon tissue compared with contractile elements of skeletal muscle or the heart, and only with very prolonged loading are significant changes in gross dimensions of the tendon observed, suggesting that habitual loading is associated with a robust change in the size and mechanical properties of human tendons. An intimate interplay between mechanical signalling and biochemical changes in the matrix is needed in tendon, such that chemical changes can be converted into adaptations in the morphology, structure and material properties.

Traumatic knee extension deficit (the locked knee): can MRI reduce the need for arthroscopy?

In the present study we investigated the validity of magnetic resonance imaging (MRI) and arthroscopy in knees with acute, traumatic extension deficit (the "locked knee"), and evaluated whether arthroscopy of knees with no mechanical pathology could be avoided by MRI evaluation. The study consisted of 50 patients who had an acute, traumatic extension deficit of the knee. All patients were submitted to MRI prior to arthroscopy. Following MRI and surgery, standardized forms were filled out, attempting to objectify the findings. The orthopaedic surgeon was not aware of the MRI result prior to surgery. Evaluating MRI, all grade-3 meniscal lesions were considered able to cause a mechanical block as well as acute partial or total anterior cruciate ligament (ACL)-ruptures. ACL-ruptures with an old appearance were not considered able to cause locking. Assuming that arthroscopy was the gold standard, the following results were calculated for the overall appearance of a lesion able to cause locking: Positive predictive value = 0.85, negative predictive value = 0.77, sensitivity = 0.95, specificity = 0.53. Two knees were erroneously evaluated with no mechanical locking at MRI (one bucket-handle lesion and one pathological synovial plica). MRI of the knee with acute, traumatic extension deficit is in the acute or subacute phase a safe method to identify the patients that have a mechanical reason for locking and therefore can benefit from arthroscopic treatment.

Collagen synthesis in human musculoskeletal tissues and skin

We have developed a direct method for the measurement of human musculoskeletal collagen synthesis on the basis of the incorporation of stable isotope-labeled proline or leucine into protein and have used it to measure the rate of synthesis of collagen in tendon, ligament, muscle, and skin. In postabsorptive, healthy young men (28 +/- 6 yr) synthetic rates for tendon, ligament, muscle, and skin collagen were 0.046 +/- 0.005, 0.040 +/- 0.006, 0.016 +/- 0.002, and 0.037 +/- 0.003%/h, respectively (means +/- SD). In postabsorptive, healthy elderly men (70 +/- 6 yr) the rate of skeletal muscle collagen synthesis is greater than in the young (0.023 +/- 0.002%/h, P < 0.05 vs. young). The rates of synthesis of tendon and ligament collagen are similar to those of mixed skeletal muscle protein in the postabsorptive state, whereas the rate for muscle collagen synthesis is much lower in both young and elderly men. After nutrient provision, collagen synthesis was unaltered in tendon and skeletal muscle, remaining at postabsorptive values (young: tendon, 0.045 +/- 0.008%/h; muscle, 0.016 +/- 0.003%/h; elderly: muscle, 0.024 +/- 0.003%/h). These results demonstrate that the rate of human musculoskeletal tissue collagen synthesis can be directly and robustly measured using stable isotope methodology.

Diagnosing patients with longstanding shoulder joint pain

OBJECTIVE

To examine the interobserver agreement of commonly used clinical tests and diagnoses in patients with shoulder pain, and the accuracy of these tests and ultrasonographic findings in comparison with arthroscopic findings.

METHODS

Eighty six patients with longstanding shoulder joint pain were "blindly" examined by two trained doctors using several clinical tests. In all patients an ultrasonographic examination was performed, and in 42 (49%) an arthroscopy.

RESULTS

Tests for impingement showed poor to moderate agreement. Tenderness of muscles, muscle weakness, and tests for labral lesion also showed poor agreement. Pain during muscle contraction showed moderate agreement. The agreement of clinical diagnoses was poor and the accuracy was low in comparison with arthroscopy. Ultrasonography was accurate in full thickness supraspinatus tendon tears, but inaccurate for partial tears and labral lesions.

CONCLUSIONS

Most clinical tests showed poor agreement. Clinical and ultrasonographic diagnoses had low accuracy in comparison with arthroscopy.

Muscle reflexes during gait elicited by electrical stimulation of the posterior cruciate ligament in humans

We investigated the influence of electrical stimulation of the posterior cruciate ligament (PCL) on the motoneuron pool of the thigh and calf muscle during gait. The study group comprised eight young men without any history of injury to the knee joints. Multistranded teflon-insulated stainless steel wires were inserted into the PCL guided by sonography and in four subjects also into the fat pad of the knee. The PCL was electrically stimulated during gait on a treadmill at heel strike and 100 ms after heel strike. Electromyographic signals were recorded with bipolar surface electrodes placed over the vastus medialis, rectus femoris, vastus lateralis, biceps femoris caput longum, and semitendinosus muscles. The stimuli consisted of four pulses delivered at 200 Hz; the stimulus amplitude was two to three times the sensory threshold. The electrical stimulation of the PCL inhibited the ongoing muscle activity in both the quadriceps and the hamstrings. The latency of the inhibition ranged between 78 and 148 ms in the quadriceps, between 88 and 110 ms in the hamstrings and between 189 and 258 ms in m. gastrocnemius. Stimulation of the fat pad of the knee did not influence the thigh and calf muscle motoneuron pool as evidenced by electromyography. The response elicited from the stimulation of the PCL was not limited to a specific muscle group but depended on ongoing muscle contraction, which suggests that the mechanoreceptors in the PCL are involved in the control of all muscles acting on the knee joint during gait.

[Diagnostic knee arthroscopy under local anesthesia in hospital. An assessment of the diagnostic reliability, course of the treatment and health care costs]

INTRODUCTION

Outpatient knee arthroscopy under local analgesia can be performed solely as a diagnostic procedure. The aim was to estimate the diagnostic precision of such arthroscopy as compared to the diagnosis made during a secondary therapeutic operation, and to describe the flow of patients and the costs of this treatment strategy.

MATERIAL AND METHODS

The records of 371 consecutive patients, who had a diagnostic knee arthroscopy performed under local analgesia, were reviewed retrospectively. The diagnosis made during the diagnostic arthroscopy (371 patients) and a later therapeutic operation (135 patients) were extracted and the patients were asked to fill in a questionnaire.

RESULTS

The diagnostic arthroscopy could not be completed in 11 cases. No further operation was necessary in 188 patients. A secondary therapeutic operation was performed in 135 patients. In only 54% of these was the same diagnosis made during the diagnostic and the therapeutic operations. Only half of the 278 patients (75%) who returned the questionnaire, found that the diagnostic procedure had been pain free.

DISCUSSION

With respect to the costs, the diagnostic arthroscopy cannot be recommended. Most economic was the strategy in which the diagnostic and therapeutic operations were performed together as an outpatient procedure. The relatively poor diagnostic precision of arthroscopy is surprising and should be kept in mind when patients continue to have unexplained complaints in the knee, despite a normal arthroscopy.

Muscular reflexes elicited by electrical stimulation of the anterior cruciate ligament in humans

Anterior cruciate ligament (ACL)-deficient knees have impaired proprioception, and, although mechanoreceptors have been found in the ACL, the existence of a reflex elicited from these receptors has not been directly demonstrated in humans. In eight patients that underwent knee arthroscopy and had no sign of ACL disease, thin wire electrodes were inserted into the proximal and mid parts of the ACL. Postoperatively, the sensory nerve fibers inside the ACL were stimulated electrically while motor activity in the knee muscles was recorded using electromyography. In seven of the eight patients, a muscular contraction of the semitendinosus muscle could be elicited with stimulus trains consisting of at least two stimuli. The latency was 95 +/- 35 ms. Stimulation during isometric contraction of either extensor or flexor muscles elicited a short, complete inhibition of the muscle activity in the contracting muscles. The latency of the inhibitory responses was 65 +/- 20 ms in the semitendinosus muscle and 70 +/- 15 ms in the rectus femoris muscle.

Sonographic guided insertion of electrodes into the cruciate ligaments of the knee

The present cadaver study examined the probability of accurate ultrasound guided insertion of electrodes into the anterior (ACL) and posterior (PCL) cruciate ligament with a fine needle. Visualisation of the structures appeared clearest from the posterior approach. From this approach 24 electrodes were inserted into the PCL and six into the ACL. From the anterior 16 were inserted into the ACL and six into the PCL. Twenty-one out of 24 electrodes were placed correctly into the PCL from the posterior view, and four out of six were placed correctly from the anterior view. From the posterior view four out of six were placed correctly in the ACL, and eight electrodes out of 16 were placed correctly from the anterior view. In conclusion, ultrasound guided insertion of electrodes from the posterior view can be performed with high accuracy into the PCL, whereas insertion into the ACL seems to be less accurate, probably because it is more difficult to visualise.

Patient compliance and effect of orthopaedic shoes

Orthopaedic shoes are individually handmade after a prescription from an orthopaedic surgeon, hence relatively expensive. Bad compliance is mentioned in the literature but not investigated. In order to evaluate patient compliance and the effect of orthopaedic shoes, 85 patients who were prescribed orthopaedic shoes at the authors' department during a 3 year period received a questionnaire concerning relief of symptoms and daily use of the shoes. The answers from 74 patients were correlated to the prescription procedure and the degree of medical follow-up. Only 60 of 74 patients used their shoes. Some 51 patients had some benefit while 23 had no effect or even worse symptoms. Some patients even used their shoes despite no symptomatic relief. However, patients who felt they were well informed about the purpose and function of their shoes had more benefit than the rest. Only 12 patients of the 74 were checked by the orthopaedic surgeon after delivery of the shoes. In conclusion the authors believe there is a great need for information to be given to the patients about the functions and limitations of orthopaedic shoes and that every patient should be offered a control check-up by the surgeon. Further investigations of the effect of orthopaedic shoes should be carried out to optimise the use of these expensive devices.

Epidemiology of acute vertebral osteomyelitis in Denmark: 137 cases in Denmark 1978-1982, compared to cases reported to the National Patient Register 1991-1993

We studied the epidemiology of acute, non-tuberculous, hematogenous vertebral osteomyelitis in Denmark during 1978-1982. 137 patients fulfilled the criteria for acute vertebral osteomyelitis. The incidence was 5/mill/year. There were no cases in the age group 20-29 years. The highest incidence was between 60-69 years (18/mill/year). The prevalence was 15 cases. The mean duration of the disease was 7 months. The lumbar spine was affected in 59%, the thoracic spine in 33% and the cervical spine in 8% of the cases. Insulin-dependent diabetes and treatment with systemic corticosteroids seemed to be significant risk factors, but not rheumatoid arthritis and abuse of alcohol or intravenous drugs. We found no demographic variables of importance for the incidence. In 46%, a primary focus was identified, urinary tract infection being the commonest. According to the National Patient Register 1991-1993, the relative number of reported patients with vertebral osteomyelitis had increased in the age group 20-49 years, compared to 1978-1982, but the incidence was highest in the group aged 60-79 years.

[Bone loss during low dose glucocorticoid treatment in patients with polymyalgia rheumatica. A double-blind, prospective comparison between prednisolone and deflazacort]

The aim of the study was to compare the long term effects of low dosage prednisolone or deflazacort treatment on bone mass in patients with polymyalgia rheumatica. The subjects were 30 patients with newly diagnosed polymyalgia rheumatica, who were allocated to treatment with prednisolone or deflazacort. Bone Mineral Content (BMC) was measured in the lumbar spine (L-BMC) and distal forearm (A-BMC) before treatment and three, six and 12 months after the start of treatment. After three months the decrease in L-BMC was significantly greater in the deflazacort group than in the prednisolone group (p < 0.05), but at six and 12 months there was not a significant difference between the two groups. There was a significant loss of BMC in all patients after 12 months: a 6.4% loss in L-BMC and a 1.8% loss in A-BMC. In conclusion, this low dose study failed to reveal any calcium sparing property of deflazacort compared with prednisolone.

Prognostic model for patients treated for colorectal adenomas with regard to development of recurrent adenomas and carcinoma

OBJECTIVE

To quantify the risk of developing recurrent adenomas or colorectal cancer for patients who had already had colorectal adenomas removed.

DESIGN

Retrospective study.

SETTING

University hospital, Denmark.

SUBJECTS

479 patients who had colorectal adenomas removed between 1958-80.

INTERVENTIONS

All patients were followed up by rectoscopy and double contrast barium enema. The survival data were analysed by Cox's proportional hazards model.

MAIN OUTCOME MEASURES

Variables of significant prognostic importance for recurrence of adenomas and the development of cancer were identified. Results. For the long term risk of recurrence of the adenoma (more than 1.5 years after removal of the first adenoma), two variables were of prognostic significance: The occurrence of synchronous adenomas or recurrent adenomas, and the sex of the patient. The model for development of colorectal cancer identified two variables of prognostic significance: the grade of dysplasia and the size of the first adenoma.

CONCLUSION

We suggest that these variables can be used in the management of patients with adenomas, particularly in developing individual follow-up regimens.