Cross-sectional study of the prevalence of hyperextension of the first metatarsophalangeal joint and its relationship to onycholysis in women with hallux valgus

BACKGROUND

Hallux Valgus (HV) deformity is associated with misalignment in the sagittal plane that affects the first toe. However, the repercussions of the first toe hyperextension in HV have been scarcely considered. The purpose of this study was to provide evidence of the association between first-toe hyperextension and the risk of first toenail onycholysis in HV.

METHODS

A total of 248 HV from 129 females were included. The extension of 1st MTP joint was measured while the patient was in the neutral position of the hallux using a two-branch goniometer. The classification of the HV severity stage was determined by the Manchester visual scale, and the height of the first toe in the standing position was measured using a digital meter. An interview and clinical examination were performed to collect information on the presence of onycholysis of the first toe.

RESULTS

Of the 248 HV studied, 100 (40.3%) had onycholysis. A neutral extension > 30 degrees was noted in 110 (44.3%) HV. The incidence of onycholysis was higher in HV type C than in type B (p = 0.044). The probability of suffering onycholysis in the right foot was 2.3 times greater when the neutral position was higher than 30 degrees (OR = 2.3; p = 0.004). However, this was not observed in the left foot (p = 0.171). Onycholysis was more frequent in HV with more than 2 cm height of the first toe (p < 0.001). For both feet, the probability of suffering onycholysis was greater for each unit increase in hallux height (right foot OR = 9.0402, p = 0.005; left foot OR = 7.6633, p = 0.010).

CONCLUSIONS

The incidence of onycholysis appears to be significantly associated with HV showing more than 30º extension, and more than 2 cm height of the first toe. Height and hyperextension of the first toe together with first toenail pathology should be mandatory in the evaluation of HV.

Rim plate in the treatment of hyperextension tibial plateau fracture: surgical technique and a series of cases

BACKGROUND

The existence of a "bare area" at the anterior plateau has been observed in cases where anteromedial and/or anterolateral proximal tibial locking plates are used for fixation in the treatment of hyperextension tibial plateau fractures (HTPF). The objective of this study is to introduce the rim plate fixation technique and evaluate its clinical efficacy.

METHODS

A retrospective analysis was conducted on HTPF patients who underwent treatment with a combination of rim plate and proximal tibial locking plate at our hospital between April 2015 and December 2019. All patients were followed up for a minimum of one year. Open reduction and internal fixation were performed using anteromedial/posteromedial and/or anterolateral approaches for all cases. The surgical strategies employed for rim plate fixation were introduced, and both radiographic and clinical outcomes were assessed.

RESULTS

Thirteen patients were enrolled in the study, with an average follow-up time of 4.3 years. Satisfactory reduction was achieved and radiographically maintained in all cases. Additionally, all patients exhibited satisfactory clinical functions, as evidenced by a mean hospital for special surgery (HSS) knee score of 96.2 ± 2.0 (range: 90-98). Furthermore, no wound complications or implant breakage were observed in this series.

CONCLUSION

The combination of the rim plate and proximal tibial plate proved to be an effective fixation configuration, resulting in satisfactory clinical outcomes.

Metacarpophalangeal hyperextension in thumb basal joint osteoarthritis: Radiological study and implications for treatment

We report a series of 95 consecutive patients operated on for total trapeziometacarpal joint replacement, screening for radiological characteristics to differentiating patients with and without preoperative MCP hyperextension. Loss of thumb column length and metacarpal head circularity on lateral view were quantified. Statistically, a combination of reduced length and circular metacarpal head was a determining factor for MCP hyperextension. We therefore believe it is essential to restore thumb column length in surgery for trapeziometacarpal osteoarthritis and to avoid trapeziectomy in patients with a circular head on lateral view. LEVEL OF EVIDENCE: III; prospective cohort study.

Hyperextension following two different designs of fixed-bearing posterior-stabilized total knee arthroplasty

PURPOSE

Hyperextension after total knee arthroplasty (TKA) is related to worse functional outcomes. Among the reported predictive factors, it is unclear whether prosthesis design affects postoperative hyperextension. Hence, our objectives were to (1) compare time-dependent changes of the extension angle following multi-radius (MR) and single-radius (SR) TKA and (2) assess predictive factors for the hyperextension.

METHODS

In this study, consecutive 136 MR TKAs and consecutive 71 SR TKAs performed by a single surgeon were reviewed. The extension angle was evaluated by digitized full-extension lateral radiographs at preoperative, 3 months and at 1 and 2 years after TKA. A positive value was defined as hyperextension. A multiple regression analysis was used to determine predictive factors for the extension angle and the risk of hyperextension > 5°.

RESULTS

The postoperative extension angle of both groups gradually increased during the first 2 years and the SR group finally progressed with 4.04° greater extension than the MR group (p < 0.01). The incidence of hyperextension > 5° in the SR group was 18.3% and for the MR group, 7.4% (p = 0.02). However, the Oxford knee scores was nonsignificant different between the groups (p = 0.15). Preoperative extension angle, sagittal femoral component angle (SFA) and SR prosthesis were predictive factors for the extension angle at 2 years after TKA and were also associated with hyperextension > 5°.

CONCLUSIONS

The extension angle of the SR group became significantly more extended than that of the MR group during the first two years after TKA. Hence, ideal extension position immediately after SR TKA may be different from that of the MR TKA prosthesis. The preoperative extension angle, SFA and SR prosthesis were factors that were associated with postoperative hyperextension.

Gender-specific difference in the recurrence of flexion contracture after total knee arthroplasty

Background

Range of motion after total knee arthroplasty (TKA) can impact patients’ daily lives. Nevertheless, flexion contracture (FC) often recurs after TKA, even upon achieving full extension intraoperatively. This study aimed to evaluate the relationship among preoperative, intraoperative, and postoperative knee extension angles, and clarify the risk factor for postoperative FC.

Methods

One hundred forty-seven knees undergoing TKA using a navigation system were evaluated. We measured the pre- and postoperative (6 months after TKA) extension angles using a goniometer, and intraoperative (before and after TKA) extension angle using a navigation system; the correlation between these angles at each time point was evaluated.

Results

The mean preoperative, intraoperative (before and after TKA) and postoperative extension angles were -9.9°, -6.8°, -0.1°, and -2.0°. Regarding intraoperative extension angle after TKA, 58 knees showed ≤ 5° hyperextension and six knees showed > 5° hyperextension. At 6 months, no cases showed hyperextension and 105 knees showed full extension. The mean intraoperative extension angle after TKA in the postoperative full extension group was 0.4°. A significant correlation was found among extension angles at each point (p<0.01, respectively). However, the intraoperative extension angle after TKA correlated with the postoperative extension angle only in females. Contrarily, the recurrence rate of FC was significantly higher in males than in females (p<0.01).

Conclusion

Intraoperative extension angles significantly correlated with pre- and postoperative extension angles in TKA. Moreover, intraoperative mild (≤ 5°) hyperextension is acceptable for postoperative full extension. There was a gender-specific difference in correlation between intra- and postoperative knee extension angles.

Level of evidence

III.

Comparison of risk for postoperative hyperextension between cruciate retaining and posterior stabilized total knee arthroplasties

INTRODUCTION

The incidence of postoperative hyperextension and factors affecting hyperextension needs to be investigated separately for cruciate retaining (CR) and posterior stabilized (PS) total knee arthroplasties (TKAs), because the mechanism for preventing hyperextension is different according to the bearing design. The purpose of the study was to compare the incidence of postoperative hyperextension between CR and PS TKAs and analyze the factors affecting the postoperative hyperextension.

METHODS

Matched 213 CR and PS TKAs with Persona^® prosthesis were retrospectively reviewed. The preoperative demographics, clinical and radiographic knee condition, and pelvic incidence were similar between groups. Appropriate knee extension (0°-5°), confirmed with a goniometer, was achieved intraoperatively. The knee sagittal angle was radiographically measured preoperatively and at 2 years postoperative. The incidence of hyperextension (sagittal angle < - 5°) was investigated. The factors affecting the postoperative hyperextension were analyzed in terms of age, sex, preoperative mechanical axis, knee sagittal angle, postoperative posterior tibial slope (PTS), change of posterior femoral offset, and pelvic incidence.

RESULTS

The knee sagittal angle was not significantly different preoperatively between CR and PS TKAs. The postoperative knee sagittal angle was 2.9° in CR TKAs and 4.4° in PS TKAs (p = 0.004). The incidence of postoperative hyperextension was 11.7% (25/213) in CR TKAs and 4.2% (9/213) in PS TKAs (p = 0.007). The preoperative sagittal angle, postoperative PTS, and pelvic incidence were the significant factors affecting the postoperative hyperextension in CR TKAs (odds ratio 0.869, 2.205, and 1.045, respectively); the preoperative sagittal angle was only the significant factor in PS TKAs (odds ratio 0.857) CONCLUSIONS: Postoperative knee hyperextension occurred more frequently and was affected by more factors in CR TKAs than PS TKAs. Efforts to avoid hyperextension and closed observation are required in TKAs performed in patients with the risk factors.

LEVEL OF EVIDENCE

III.

Modified anterior midline approach to treat hyperextension bicondylar tibial plateau fractures: Surgical technique and clinical experience with 18 cases

BACKGROUND

We evaluated the modified anterior midline approach and its efficacy for hyperextension bicondylar tibial plateau (HEBTP) fractures.

METHODS

From 2015 to 2019, 18 patients with HEBTP fractures with just little posterior cortical displacement were treated using the modified anterior midline approach. The operative protocols are fully described in this article, and the following parameters: articular step-off height (ASH), posterior tibial slope angle (pTSA), and medial tibial plateau angle (mTPA) were measured perioperatively and at the final follow-up. We also recorded the Rasmussen score and range of motion (ROM) to assess knee joint function at the final follow-up.

RESULTS

No complications, such as percutaneous nerve damage, infection, skin necrosis, and internal fixation breakage or loosening occurred perioperatively. The mean time for bony union was 13.7 weeks, and the mean preoperative ASH of the anterior cortex was 4.49 mm; this was restored to its normal height after surgery. The mean preoperative pTSA and mTPA were - 5.89° and 81.69°, respectively, compared with 3.89° and 87.91°, respectively, postoperatively. Comparing the postoperative and final follow-up radiographs, there were no significant differences in ASH, pTSA, and mTPA (P < 0.05). The average Rasmussen score was 27.2 (range, 23-29) at the final follow-up. Excellent results were achieved in 14 (77.8%) patients and good in 4 (22.2%) patients. The mean ROM in flexion was 123.2° and 2.9° in extension at the final follow-up.

CONCLUSIONS

This study suggested that the modified anterior midline approach is a reasonable alternative for HEBTP fracture repair.

Central Cord Syndrome Redefined

This article reviews the historical origins of central cord syndrome (CCS), the mechanism of injury, pathophysiology, and clinical implications. CCS is the most common form of incomplete spinal cord injury. CCS involves a spectrum of neurologic deficits preferentially affecting the hands and arms. Evidence suggests that in the twenty-first century CCS has become the most common form of spinal cord injury overall. In an era of big data and the need to standardize this particular diagnosis to unite outcome data, we propose redefining CCS as any adult cervical spinal cord injury in the absence of fracture/dislocation.

The deep medial femoral sulcus sign: does it exist?

OBJECTIVE

To determine the normal depth of the medial femoral sulcus on lateral radiographs of the knee and determine if abnormal deepening of the medial femoral sulcus exists as a radiographic indicator of intra-articular knee abnormalities.

MATERIALS AND METHODS

A retrospective search was performed over a period of 10 years to identify all individuals with a bone contusion of the anterior medial femoral condyle at MR imaging. Study patients had documented acute knee injuries and radiographs 6 weeks or less prior to their MR. A control group had normal MR exams and radiographs 6 weeks or less prior to their MR. Two fellowship-trained musculoskeletal radiologists independently measured the depth of the medial femoral sulcus on lateral radiographs blinded to control or study individuals.

RESULTS

The study group consisted of 76 patients (57 men, 19 women; age range, 18-50 years; mean age, 27 years) and 92 control patients (33 men, 59 women; age range, 18-46 years; mean age 26 years). Sulcus depth was (0-2.3 mm reader 1 and 0-1.7 mm reader 2 for controls; 0-2.2 mm reader1 and 0-1.8 mm reader 2 for study patients). No significant difference in sulcus depth was identified between the control and study groups. Inter-reader agreement was very strong. The most common cause of injury in the study group was motor vehicle accidents followed by hyperextension and twisting injuries of the knee.

CONCLUSION

The normal medial femoral sulcus ranges in depth from 0 to 2.3 mm. Although impaction of the sulcus does occur following knee injuries, the sulcus does not deepen.

Suicidal jumper's fracture reduced with hyperextension and the joystick method: A case report

Suicidal jumper's fractures are transversal fractures of the upper sacrum. The treatment for this type of fracture remains controversial. We present a case of a Roy-Camille type 2 suicidal jumper's fracture treated with reduction by hyperextension of the lumbosacral junction, the joystick method, and percutaneous fixation on the day of injury. After the operation, the sacral canal at the S2 level was enlarged and both lower extremities began to move gradually. At 19 days after the injury, direct decompression via sacral laminectomy was performed to promote further neurological improvement. At 10 months after the injury, cauda equina syndrome and radicular symptoms were completely resolved. Considering its minimal invasiveness, we recommend trying hyperextension and the joystick method to treat Roy-Camille type 2 suicidal jumper's fractures on the day of injury.

Knee laxity, lateral meniscus tear and distal femur morphology influence pivot shift test grade in ACL injury patients

PURPOSE

Although several factors have been considered to be associated with pivot shift test grade in ACL injured patients, a conclusion regarding which factors contribute to the pivot shift test grade has not been reached. The purpose of this study was to identify factors associated with preoperative pivot shift test grade.

METHODS

Three hundred and sixty-six consecutive patients who underwent ACL reconstruction in our hospital were enrolled in the study. Patients were divided into two groups on the basis of preoperative pivot shift test grade (Mild: grade 0-3, Severe: grade 4-6). First, 13 independent variables (age, gender, period from injury to surgery, hyperextension, KT measurement, contralateral side pivot shift test grade, medial and lateral tibial slope, lateral condyle length, lateral condyle height, distal femoral condyle offset, medial and lateral meniscus tear) were analyzed by one-way ANOVA and Chi-squared test. Binary Logistic regression was then performed based on the results of univariate analyses (independent variables of p < 0.2 were included).

RESULTS

Hyperextension, lateral meniscus tear, contralateral side pivot shift test grade, distal femoral condyle offset and KT measurement were identified as risk factors for preoperative pivot shift grade via logistic regression analysis.

CONCLUSION

The current study revealed that hyperextension, lateral meniscus tear, contralateral side pivot shift test grade, distal femoral condyle offset and anterior instability were associated with preoperative pivot shift grade. Patients with above factors that cannot be modified during surgery may need special consideration when ACL reconstruction is performed, as greater preoperative pivot shift has been proven to be a risk factor for residual pivot shift after ACL reconstruction.

LEVEL OF EVIDENCE

III.

Canine Carpal Injuries: From Fractures to Hyperextension Injuries

The canine and feline carpus is a complex arrangement of bones, ligaments, and joint spaces that functions as a ginglymus joint to provide carpal flexion and extension. Given the demanding biomechanical demands on the carpus during weight bearing, a variety of region-specific pathology, often secondary to trauma, are reported. This review details carpal anatomy, biomechanical understandings, and current evidence surrounding carpal pathology and its management. Partial carpal arthrodesis and pancarpal arthrodesis outcomes are reviewed in detail.

Metacarpophalangeal joint instability in trapeziometacarpal osteoarthritis: A systematic review

Thumb metacarpophalangeal instability is commonly found in conjunction with trapeziometacarpal osteoarthritis. If not corrected, it can have detrimental effects on the outcome. The authors describe the two types of metacarpophalangeal deformities - hyperextension and valgus - their pathophysiology and the surgical repair techniques available to surgeons. An algorithm for treating this instability is presented.

Dimensional Changes of Lumbar Intervertebral Foramen in Direct Anterior Approach-Specific Hyperextension Supine Position

Objective

To investigate the changes in the lumbar intervertebral foramen (LIVF) dimensions from neutral supine to direct anterior approach (DAA)‐specific hyperextension supine position through a standardized three‐dimensional (3D) reconstruction computerized tomography (CT) method.

Methods

A total of 35 healthy volunteers (18 men and 17 women) were included in this retrospective study. The mean age of enrolled subjects was 28.9 ± 5.0 years. In September 2018, all the individuals underwent a 3D CT scan of the lumbar spine in neutral and 30° hyperextension supine positions, which mimicked the patient’s position in DAA total hip arthroplasty (THA). The dimensions of the LIVF, including foraminal area, height, and width, were measured on 3D reconstructed CT models at all lumbar foraminal levels. Foraminal area was defined as the area bounded by the adjacent superior and inferior vertebral pedicles, the posterosuperior boundary of the inferior vertebral body, the surface of the intervertebral disc posteriorly, the posteroinferior boundary of the superior vertebral body, and the surface of the ligamentum flavum anteriorly. Foraminal height was defined as the longest distance between the border of the superior and the inferior pedicle. Foraminal width was defined as the shortest distance between the posteroinferior edge of the superior vertebrae and the opposing boundary. Subgroup analysis and multiple linear regression were used to evaluate the relationship between percentage changes of the LIVF dimensions and side, sex, and age.

Results

The LIVF dimensions varied significantly between the two positions at all levels (P < 0.05). From neutral to hyperextension supine position, the foraminal area reduced by 20.1% at lumbar 1–2 (L_1–2), 22.6% at L_2–3, 19.9% at L_3–4, 18.1% at L_4–5, and 12.0% at lumbar 5–sacral 1 (L₅–S₁) level, respectively; the foraminal height reduced by 9.5% at L_1–2, 10.5% at L_2–3, 9.5% at L_3–4, 9.6% at L_4–5, and 6.1% at L₅–S₁ level, respectively; the foraminal width reduced by 12.8% at L_1–2, 14.5% at L_2–3, 13.0% at L_3–4, 10.4% at L_4–5, and 8.4% at L₅–S₁ level, respectively. The changes in LIVF dimensions were biggest at L_2–3 level and smallest at L₅–S₁ level. Subgroup analysis showed that there were no significant differences in the percentage changes of LIVF dimensions between the sexes and sides (P > 0.05). Multiple linear analysis showed that the percentage changes of LIVF dimensions were not related to side, sex, and age (P > 0.05).

Conclusion

The dimensions of the LIVF showed significant decrease at all levels in the DAA‐specific hyperextension supine position compared with the neutral supine position, and the percentage changes of LIVF dimensions were not influenced by side, sex, and age.

[Avulsion of the extensor carpi radialis longus et brevis tendons with avulsion fracture at the base of the third metacarpal bone : A rare case]

This article presents the case of a traumatic avulsion of the extensor carpi radialis longus et brevis tendons with avulsion fracture at the base of the third metacarpal bone. Surgery as soon as possible is recommended in order to avoid retraction of the tendon.

Numerical investigation of the relative effect of disc bulging and ligamentum flavum hypertrophy on the mechanism of central cord syndrome

BACKGROUND

The pathogenesis of the central cord syndrome is still unclear. While there is a consensus on hyperextension as the main traumatic mechanism leading to this condition, there is yet to be consensus in studies regarding the pathological features of the spine (intervertebral disc bulging or ligamentum flavum hypertrophy) that could contribute to clinical manifestations.

METHODS

A comprehensive finite element model of the cervical spine segment and spinal cord was used to simulate high-speed hyperextension. Four stenotic cases were modelled to study the effect of ligamentum flavum hypertrophy and intervertebral disc bulging on the von Mises stress and strain.

FINDINGS

During hyperextension, the downward displacement of the ligamentum flavum and a reduction of the spinal canal diameter (up to 17%) led to a dynamic compression of the cord. Ligamentum flavum hypertrophy was associated with stress and strain (peak of 0.011 Mpa and 0.24, respectively) in the lateral corticospinal tracts, which is consistent with the histologic pattern of the central cord syndrome. Linear intervertebral disc bulging alone led to a higher stress in the anterior and posterior funiculi (peak 0.029 Mpa). Combined with hypertrophic ligamentum flavum, it further increased the stress and strain in the corticospinal tracts and in the posterior horn (peak of 0.023 Mpa and 0.35, respectively).

INTERPRETATION

The stenotic typology and geometry greatly influence stress and strain distribution resulting from hyperextension. Ligamentum flavum hypertrophy is a main feature leading to central cord syndrome.

Effect of hyperextension of the neck (rose position) on cerebral blood oxygenation in patients who underwent cleft palate reconstructive surgery: prospective cohort study using near-infrared spectroscopy

OBJECTIVES

To facilitate the best approach during cleft palate surgery, children are positioned with hyperextension of the neck. Extensive head extension may induce intraoperative cerebral ischemia if collateral flow is insufficient. To evaluate and monitor the effect of cerebral blood flow on cerebral tissue oxygenation, near-infrared spectroscopy has proved to be a valuable method. The aim of this study was to evaluate and quantify whether hyperextension affects the cerebral tissue oxygenation in children during cleft palate surgery.

MATERIALS AND METHODS

This prospective study included children (ASA 1 and 2) under the age of 3 years old who underwent cleft palate repair at the Wilhelmina Children's Hospital, in The Netherlands. Data were collected for date of birth, cleft type, date of cleft repair, and physiological parameters (MAP, saturation, heart rate, expiratory CO₂ and O₂, temperature, and cerebral blood oxygenation) during surgery. The cerebral blood oxygenation was measured with NIRS.

RESULTS

Thirty-four children were included in this study. The majority of the population was male (61.8%, n = 21). The mixed model analyses showed a significant drop at time of Rose position of - 4.25 (69-74 95% CI; p < 0.001) and - 4.39 (69-74 95% CI; p < 0.001). Postoperatively, none of the children displayed any neurological disturbance.

CONCLUSION

This study suggests that hyperextension of the head during cleft palate surgery leads to a significant decrease in cerebral oxygenation. Severe cerebral desaturation events during surgery were uncommon and do not seem to be of clinical relevance in ASA 1 and 2 children.

CLINICAL RELEVANCE

There was a significant drop in cerebral oxygenation after positioning however it is not clear whether this drop is truly significant physiologically in ASA 1 and 2 patients.

Outcomes of Chronic Turf Toe Repair in Non-athlete Population: A Retrospective Study

BACKGROUND

Turf toe injuries, though most common in athletes, can also occur in non-athletes. No study exists in the current literature investigating operative outcomes in non-athlete patients with chronic turf toe injury. In this study, we present our outcomes on operatively treated turf toe injuries in non-athletes in the only cohort yet studied.

METHODS

Using ICD-10 codes, we assembled a cohort of 12 patients who underwent operative repair of chronic turf toe injury from January 2012 through January 2018 at the investigating institution. These 12 patients were evaluated to determine demographic information, method of injury, length of time from injury to surgery, clinical and radiologic characteristics of the injury, and operative outcomes including mean preoperative and postoperative VAS (Visual Analog Scale) scores, preoperative and postoperative FFI (Foot Function Index) scores, and postoperative complications.

RESULTS

On initial clinical presentation, all 12 patients had local tenderness with associated painful range of motion. Four patients had restricted range of motion, all patients had a positive Lachman test, two had local edema, and eight had hallux valgus deformity. Mean VAS improved from 4.6 (range 2-9) to 1 (range 0-4). Mean FFI improved from 102.5 (range 56-177) to 61.75 (range 23-144). All patients had a negative Lachman test at final follow-up. No patients developed major complications or required revision surgery.

CONCLUSIONS

Our study is the first to investigate operative outcomes following chronic turf toe injury in non-athlete patients. Based on our study, surgeons and patients can expect significant improvement in overall pain and function following surgery.

Risk factors of hyperextension and its relationship with the clinical outcomes following mobile-bearing total knee arthroplasty

INTRODUCTION

To evaluate the incidence and risk factors of postoperative hyperextension after mobile-bearing total knee arthroplasty (TKA) and its clinical outcomes.

MATERIALS AND METHODS

This retrospective case-control study included 387 knees of primary TKA patients after a 5-year follow-up. The clinical outcomes and radiographs including posterior condylar offset (PCO), femur and tibial slope angle and its discrepancy were evaluated. The patients were divided into two groups (group 1: non-hyperextension, group 2: hyperextension). An extension greater than 5° measured using a goniometer at the final follow-up was defined as hyperextension. Logistic and linear regression analyses were performed.

RESULTS

Overall, 43 knees (11.1%) with hyperextension were observed at the last follow-up. There was no significant difference between groups in terms of the clinical outcomes although the functional scores were worse in group 2. There was no significant difference in the postoperative radiologic evaluation except for a change in PCO (group 1 vs. group 2; - 0.2 mm ± 3.8 vs. - 2.4 mm ± 3.0, p = 0.003), distal femoral resection slope angle (- 9.1° ± 2.1 vs. - 12.1° ± 1.7, p < 0.000) and discrepancy of the slope angle (0.3° ± 4.5 vs. - 3.6° ± 3.9, p < 0.000). The change in PCO [odds ratio (OR) 0.86, p = 0.012], discrepancy of the slope angle (OR 0.8136, p = 0.000) and the preoperative mechanical femorotibial angle (OR 1.09, p = 0.003) were associated with hyperextension.

CONCLUSION

Mobile-bearing TKA with hyperextension over 5° showed worse functional outcomes at the mid-term follow-up, even though no serious complications were observed. Care should be taken to maintain the posterior condylar offset and to match the resection angles in femur and tibia due to the risk of hyperextension and worse functional outcomes.

LEVEL OF EVIDENCE

IV.

Bicruciate lesion biomechanics, Part 2-treatment using a simultaneous tensioning protocol: ACL fixation first is better than PCL fixation first to restore tibiofemoral orientation

PURPOSE

An uncommon technique for bicruciate ligament reconstruction involving simultaneous tensioning of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) grafts with ACL graft fixation first has been pointed out as superior to the "gold-standard" PCL graft fixation first. The purpose of this study was to compare tibiofemoral biomechanics between ACL fixation first and PCL fixation first in a simultaneous tensioning protocol for bicruciate ligament reconstruction.

METHODS

12 fresh-frozen cadaveric knees (six matched pairs) were tested using a custom testing system. Neutral tibial position representing tibiofemoral orientation, anterior-posterior (AP) tibial translation, varus-valgus laxity, and internal-external rotation were measured using a Microscribe 3DLX at 0°, 30°, 60°, and 90° of knee flexion. The following knee conditions were evaluated: intact, bicruciate deficient and following bicruciate reconstruction. A simultaneous tensioning protocol was used for bicruciate reconstruction and PCL fixation first was compared to ACL fixation first. PCL graft fixation was always performed at 90° of flexion and ACL graft fixation was always performed at full extension.

RESULTS

ACL fixation first achieved a tibiofemoral orientation closer to the intact knee than PCL fixation first at 90° flexion (1.8 ± 1.6 mm versus 6.1 ± 3.2 mm, p = 0.016). PCL fixation first had a larger decrease in AP translation than ACL fixation first at 30° flexion (64.6 ± 3.5% vs. 58.3 ± 2.4%, p = 0.01). No significant differences were found for varus/valgus, external-internal rotation decrements after bicruciate reconstruction nor for AP translation, varus/valgus and internal/external rotation increase after bicruciate lesion comparing ACL fixation first to PCL fixation first.

CONCLUSION

Bicruciate ligament reconstruction using a simultaneous tensioning protocol with ACL fixation first resulted in a closer to normal tibiofemoral orientation. This study will help guide surgeons in decision making for the graft tensioning protocol and fixation sequence in a bicruciate ligament reconstruction.

LEVEL OF EVIDENCE

V therapeutic study.

Benefits of Additional Procedures for Metacarpophalangeal Hyperextension on Simple Trapeziectomy in Thumb Basal Osteoarthritis: A Biomechanical Cadaver Study

Background: Patients with advanced osteoarthritis of the first carpometacarpal joint (CMC-1) may develop hyperextension of the first metacarpophalangeal joint (MCP-1). No clear clinical benefice has been reported consecutively to the surgical treatment of the MCP-hyperextension combined to a trapeziectomy. The reason of the missing benefit may be due to changes in the thumb position impairing the thumb stability secondary to the surgical procedures. We assessed changes in the transmission of forces at the thumb's end phalanx following a trapeziectomy combined with the surgical adjustment of the hyperextension of the MCP-1-joint in a biomechanical investigation using cadavers. Methods: The thumb muscles were loaded with nylon cables connected to a tension meter in 8 forearm cadavers. A 6-axis force sensor assessed the termino-lateral key-pinch orthogonal strength vectors at the level of the thumb distal phalanx prior to any surgery, and following a simple trapeziectomy, a trapeziectomy combined to a MCP-1-capsulodesis and the transfer of the extensor pollicis brevis over the metacarpal-1 head, or to an MCP-1-arthrodesis. Results: Combination of the trapeziectomy with the MCP-1- joint palmar capsulodesis and EPB-transfer or with a MCP-arthrodesis in neutral pronation-supination resulted in a significant shift of the thumb in pronation-abduction with respect to the preoperative assessment. The lowest shift was achieved when performing the arthrodesis in 20° supination or by overloading of the adductor pollicis. Conclusions: Combining the trapeziectomy with surgeries addressing the MCP-1-joint hyperextension induced a shift of the thumb in pronation-abduction that could impair the key-pinch stability. When considering additional procedures for MCP-1-joint hyperextension deformities, it should be recommended to fix the EPB-tendon on the radial aspect of the metacarpal head if a tendon transfer is considered, otherwise the MCP joint arthrodesis should be performed in supinated position, in order to achieve lateral key-pinch stability.

Simon's hemorrhages in a case of a fatal construction site accident as the result of body hyperextension in the upside-down position - a possible reconstruction of the injury mechanism

An accident occurred at a construction site and a 27-year-old worker was fatally injured. Equipped with personal protective equipment (helmet and a safety belt), he was standing on an 8-meter-high platform holding a large hose that was attached to a pipe connected to a concrete pump truck. Whilst in use the pipe broke and the hose sent the man flying with force, knocking down the platform railing. Autopsy examination showed that man fell to the ground landing on his head. Prominent Simon's hemorrhages were noted on the L5-S1 and L4-L5 intervertebral discs. When the hose threw the man from the platform, for one brief moment he was suspended in the air, with the safety belt tied firmly to his waist. Simon's hemorrhages most probably emerged at that moment, due to forceful hyperextension and traction of the body in the upside-down position. A relatively unexpected appearance of Simon's hemorrhages contributed to the reconstruction of the injury mechanism.

Do trapeziometacarpal prosthesis provide better metacarpophalangeal stability than trapeziectomy and ligamentoplasty?

BACKGROUND

No surgical management is better than another regarding functional recovery for trapeziometacarpal joint osteoarthritis. Metacarpophalangeal (MCP) hyperextension, directly due to the shortening of thumb height, appears to be a factor of poor prognosis.

HYPOTHESIS

MCP hyperextension can be corrected by implantation of a trapeziometacarpal prosthesis (TMP), as opposed to trapeziectomy and ligamentoplasty (TL), and pinch strength is greater with TMP in this indication.

MATERIAL AND METHODS

Sixty-nine patients (41 TMP and 28 TL) were retrospectively evaluated. The following were evaluated: pain, mobility of the metacarpophalangeal joints, palmar grip and pinch strength. Thumb height was measured on radiographs as a post/preoperative ratio.

RESULTS

The mean follow-up was 20 months (6-38). The TMP group showed greater reduction of the metacarpophalangeal hyperextension in all hyperextension groups, especially hypertension >30°, compared with TL. The TMP group provided significant greater pinch strength in all the subgroups with preoperative MCP hyperextension. Patient with postoperative MCP hyperextension had a significant lower grip and pinch strength compared with patient without MCP hyperextension. Radiographic analysis showed that thumb height changes were related to the degree of preoperative hyperextension. Postoperatively, patients with postoperative MCP hyperextension had a significant lower thumb height than patient without MCP hyperextension.

DISCUSSION

Metacarpophalangeal hyperextension appears to be a factor of poor prognosis for surgical treatment of trapeziometacarpal osteoarthritis when it is not managed. TMP provides better metacarpophalangeal stabilization by restoring thumb length and would avoid surgery on the metacarpophalangeal joint. TMP may be recommended in patients having symptomatic trapeziometacarpal joint osteoarthritis and MCP joint hyperextension.

LEVEL OF EVIDENCE

III, retrospective observational case control study.

Knee hyperextension does not adversely affect dynamic in vivo kinematics after anterior cruciate ligament reconstruction

PURPOSE

To evaluate the effect of knee hyperextension on dynamic in vivo kinematics after anterior cruciate ligament reconstruction (ACL-R).

METHODS

Forty-two patients underwent unilateral ACL-R. Twenty-four months after surgery, subjects performed level walking and downhill running on a treadmill while dynamic stereo radiographs were acquired at 100 (walking) and 150 Hz (running). Tibiofemoral motion was determined using a validated model-based tracking process, and tibiofemoral translations/rotations were calculated. The range of tibiofemoral motions from 0 to 10% of the gait cycle (heel strike to early stance phase) and side-to-side difference (SSD) were calculated. Maximum knee extension angle of ACL-reconstructed knees during walking was defined as active knee extension angle in each subject. Correlations between maximum knee extension angle and tibiofemoral kinematics data were evaluated using Spearman's rho (P < 0.05).

RESULTS

No significant correlation was observed between maximum knee extension angle and the range of anterior tibial translation during functional activities in the ACL-R knees. Maximum knee extension angle was weakly correlated with internal tibial rotation range in ACL-R knee during running (ρ = 0.376, P = 0.014); however, maximum extension angle was not correlated with SSD of internal tibial rotation. SSD of internal tibial rotation was -0.4° ± 1.9° (walking), -1.6° ± 3.1° (running), indicating ACL-R restored rotatory knee range of motion during functional movements.

CONCLUSION

Knee hyperextension was not significantly correlated with greater SSD of anterior translation and internal rotation. The clinical relevance is that knee hyperextension does not adversely affect kinematic outcomes after ACL-R and that physiologic knee hyperextension can be restored after ACL-R when knee hyperextension is present.

LEVEL OF EVIDENCE

III.

A case of asystole from carotid sinus hypersensitivity during patient positioning for thyroidectomy

Background

We present a case of a patient with multinodular goiter disease who suffered asystole during head hyperextension for surgical positioning on the operational table.

Case Presentation

Manipulation of carotid sinus may trigger bradycardia or even asystole even in patients without prior history of carotid sinus hypersensitivity. The time proximity between patient positioning and asystole, the late responsiveness to atropine, the immediate increase of heart rate after head elevation and the lack of any other trigger factor or prior history support the hypothesis of carotid sinus syndrome.

Conclusions

Head hyperextension during surgical positioning is not only responsible for jeopardizing blood flow to spinal cord and brainstem but may trigger reflexes, as well, even in patients without prior neck pathology.

Floating lumbar spine: proposed mechanism with review of literature

Hyperextension injuries of lumbar spine resulting in lumbosacral dislocation are a rare entity. We report a case of a 60-year-old male who presented to us in outpatient department with history of trivial fall from bicycle with fracture through the pedicles extending from L2 to L5 with lumbosacral dislocation with free floating posterior elements with intact neurology. This is the first case report of 4 level extension compression injury with lumbosacral dislocation leading to floating lumbar spine to the best of author's knowledge. Treatment consists of reduction of the lumbosacral dislocation first and fusion of the disc space followed by reduction of the other fractures proximally. These injuries may present with a trivial trauma in spondylotic spine in elderly patients. MRI and CT scan should be done early to identify it, reduce and fix it, as in many cases with trivial trauma there may be no neural deficit.

Reduction of genu recurvatum through adjustment of plantarflexion resistance of an articulated ankle-foot orthosis in individuals post-stroke

BACKGROUND

Genu recurvatum (knee hyperextension) is a common issue for individuals post-stroke. Ankle-foot orthoses are used to improve genu recurvatum, but evidence is limited concerning their effectiveness. Therefore, the aim of this study was to investigate the effect of changing the plantarflexion resistance of an articulated ankle-foot orthosis on genu recurvatum in patients post-stroke.

METHODS

Gait analysis was performed on 6 individuals post-stroke with genu recurvatum using an articulated ankle-foot orthosis whose plantarflexion resistance was adjustable at four levels. Gait data were collected using a Bertec split-belt instrumented treadmill in a 3-dimensional motion analysis laboratory. Gait parameters were extracted and plotted for each subject under the four plantarflexion resistance conditions of the ankle-foot orthosis. Gait parameters included: a) peak ankle plantarflexion angle, b) peak ankle dorsiflexion moment, c) peak knee extension angle and d) peak knee flexion moment. A non-parametric Friedman test was performed followed by a post-hoc Wilcoxon Signed-Rank test for statistical analyses.

FINDINGS

All the gait parameters demonstrated statistically significant differences among the four resistance conditions of the AFO. Increasing the amount of plantarflexion resistance of the ankle-foot orthosis generally reduced genu recurvatum in all subjects. However, individual analyses showed that the responses to the changes in the plantarflexion resistance of the AFO were not necessarily linear, and appear unique to each subject.

INTERPRETATIONS

The plantarflexion resistance of an articulated AFO should be adjusted to improve genu recurvatum in patients post-stroke. Future studies should investigate what clinical factors would influence the individual differences.

Does the hyperextension maneuver prevent knee extension loss after arthroscopic anterior cruciate ligament reconstruction?

Background

Disruption of the anterior cruciate ligament (ACL) is one of the most frequent musculoskeletal injuries affecting physically active men and women. In the United States, an estimated 200,000 ACL reconstructions are performed annually. One of the most common complications of ACL reconstruction is loss of extension. The purpose of this study was to assess the effects of the hyperextension maneuver on preventing knee extension loss after arthroscopic ACL reconstruction.

Materials and methods

In this prospective randomized clinical trial study, 100 adult patients with a documented complete ACL tear were randomized to two groups. All patients underwent arthroscopic ACL reconstruction with quadrupled semitendinosus and gracilis autograft by the senior author based on the same technique and instruments. However, the hyperextension maneuver was only performed in 50 patients during autograft fixation on the tibial side (case group). The postoperative rehabilitation protocol was similar for both groups. The knee range of motion and extension limit was evaluated at 2, 6, 12, and 24 weeks and at 1 year postoperatively.

Results

One hundred patients (88 male and 12 female) aged from 17−36 years (average 26.9 years) were included in our study. The two groups were similar regarding age, sex, and dominant side involvement (P >0.4).The difference between the two groups was significant only at 2 weeks (P <0.02). After 2 weeks, although the rate of limited extension was higher in the control group, no significant difference was seen between the groups.

Conclusion

Although the hyperextension technique during graft fixation on the tibial side may induce better range of motion in the first 2 weeks after ACL reconstruction surgery, this effect is not significant after 2 weeks.

Level of evidence

Therapeutic level II.

Hyper extension-internal rotation (HERI): A new test for anterior gleno-humeral instability

BACKGROUND

Anterior shoulder dislocation causes injury to the inferior gleno-humeral ligament (IGHL) and capsule. Clinical manoeuvres currently used to evaluate the IGHL test for, and may induce, apprehension. We developed the hyper extension-internal rotation (HERI) test to assess the IGHL and inferior capsule without causing apprehension or inducing a risk of gleno-humeral dislocation.

HYPOTHESIS

The HERI test is easy to perform and reproducible, induces no risk of gleno-humeral dislocation during the manoeuvre, and causes no apprehension in the patients.

MATERIAL AND METHODS

We studied 14 fresh cadaver shoulders. Each specimen was positioned supine with the lateral edge of the scapula on the table and the upper limb hanging down beside the table under the effect of gravity. This position produced hyperextension and internal rotation of the gleno-humeral joint. For each shoulder, the range of extension (°) was measured before and after isolated IGHL section. Then, we performed the HEIR test in 50 patients with chronic unilateral anterior gleno-humeral instability and we compared the range of extension between the normal and abnormal sides.

RESULTS

In the cadaver study, isolated IGHL section increased the angle of extension by a mean of 14.5° (11°-18°) compared to the pre-injury values. In the clinical study, the mean difference in extension angles between the normal and abnormal sides was 14.5°. The patients reported no apprehension during the HERI test.

CONCLUSION

The angle of extension increases after section or injury of the IGHL in cadaver specimens and patients, respectively. When the inferior capsule and IGHL are damaged, the angle of extension increases compared to the normal side. Lesions to these structures can be evaluated clinically by performing the HERI test.

LEVEL OF EVIDENCE

III.

Proprioceptive acuity into knee hypermobile range in children with joint hypermobility syndrome

BACKGROUND

Children with Joint Hypermobility Syndrome (JHS) have reduced knee joint proprioceptive acuity compared to peers. Altered proprioception at end of range in individuals with JHS is hypothesised to contribute to recurrent joint injuries and instability. This study aims to provide the first objective comparison of functional knee joint proprioceptive acuity in hyperextension range compared to early flexion range in children with JHS.

METHODS

Active, weight-bearing knee joint proprioceptive acuity in both hyperextension and early flexion range was tested with a purpose-built device. Proprioceptive acuity was measured using the psychophysical method of constant stimuli to determine ability to discriminate between the extents of paired active movements made to physical stops. The smallest difference in knee range of motion that the child is able to correctly judge on at least 75% of occasions, the Just Noticeable Difference (JND), was calculated using Probit analysis. Knee pain, muscle strength, amount of physical activity and patient demographic data were collected.

RESULTS

Twenty children aged 8-16 years with JHS and hypermobile knees participated. Eleven children demonstrated better proprioceptive acuity in flexion, and 9 in hyperextension (z = 0.45, p = 0.63). Matched pairs t-test found no significant difference in children's ability to discriminate between the same extents of movement in the hyperextension or flexion directions (mean JND difference 0.11°, 95% CI -0.26° - 0.47°, p = 0.545). However, 3 children could not discriminate movements in hyperextension better than chance. Proprioceptive acuity scores were positively correlated between the two directions of movement (r = 0.55, p = 0.02), with no significant correlations found between proprioceptive acuity and age, degree of hypermobility, muscle strength, pain level, amount of physical activity or body mass index centile (r = -0.35 to -0.03, all p ≥ 0.13).

CONCLUSION

For a group of children with JHS involving hypermobile knees, there was no significant difference between knee joint proprioceptive acuity in early flexion and in hypermobile range when measured by a functional, active, weight-bearing test. Therefore, when implementing a proprioceptive training programme, clinicians should focus training throughout knee range, including into hyperextension. Further research is needed to determine factors contributing to pain and instability in hypermobile range.

Acute hyperextension/valgus trauma to the elbow in top-level adult male water polo goalkeepers: a cause of osteochondritis disecans of the capitellum?

We report on 2 cases of hyperextension/valgus elbow injuries in two adult male national team water polo goalkeepers. Both were healthy and had never sustained any major injuries of the elbow. Mechanism and type of injury in both of them was identical. Different medical treatment protocols of these injuries possibly have led to different outcomes, with one of them developing osteochondritis dissecans (OCD). Inadequate medical treatment of acute impact elbow injuries could lead to osteochondritis disecans of the elbow in top-level adult male water polo goalkeepers.