Outcomes of acute versus delayed total hip arthroplasty following acetabular fracture

PURPOSE

Post-traumatic arthritis is known complication following acetabular fracture. The aim was to compare mid- to long-term outcomes of acute THA (aTHA) for acetabular fracture and delayed THA (dTHA) following failure of ORIF or conservative management.

METHODS

We retrospectively analysed 60 THA (21 aTHA; 39 dTHA) performed for acetabular fracture between 2004 and 2014 in 60 patients with a mean age of 59 years (20-94). Functional and Radiographic outcomes were assessed at a mean follow-up of 5 years (2-13) utilizing Oxford, Harris Hip (HHS), and Postel Merle d'Aubigné (PMA) scores and Brooker classification.

RESULTS

The mean HHS (73), Oxford (32) and PMA (12) scores were significantly lower in the aTHA group. Acute THA was significantly associated with lower postoperative Oxford (β = -4.2), HHS (β = -7.8), and PMA (β = -2.2) scores at mean 5 years (2-13). Eleven patients returned to the operating room. There were no significant differences between THA performed in acute or delayed fashion. The two primary reasons for revision were periprosthetic joint infection (n = 5) and aseptic loosening (n = 4). Survivorship free from reoperation at 10 years was 91% and 82% for aTHA and dTHA, respectively (p = 0.24). Increased PMA scores were associated with decreased overall survival of the THA free from reoperation (HR = 0.60). The degree of heterotopic ossification was significantly higher in the aTHA group (p < 0.001).

CONCLUSION

Acute THA in the setting of acetabular fracture is a technically challenging procedure. However, in the present series, aTHA provided satisfactory immediate stability and good survivorship at 10 years in a medically vulnerable patient population.

LEVEL OF EVIDENCE

Level 3; Therapeutic study.

The accuracy of MRI for the diagnosis of ramp lesions

OBJECTIVES

To assess the diagnostic accuracy of MRI in diagnosing ramp lesions in patients with an acute lesion of the anterior cruciate ligament (ACL).

MATERIALS AND METHODS

All consecutive patients over 15 years of age who underwent surgical repair of the ACL at a single hospital between January and May 2019, with MRI data available, were included in this retrospective study, except patients who had previous knee surgery. The gold standard was arthroscopic evaluation. Two trained radiologists with 5 and 14 years of experience did a blinded review of the MRIs. The following pathological signs were studied: complete fluid filling between the capsule and the posterior horn of the medial meniscus, irregular appearance of the posterior wall of the medial meniscus, oedema of the capsule, fluid hyperintensity in contact with the medial meniscus and anterior subluxation of the medial meniscus. Logistic regressions in univariate then multivariate analysis were carried out and measures of diagnostic accuracy and interobserver agreement were calculated with R software (version 3.6).

RESULTS

Fifty-seven patients were included. Twelve had a ramp lesion diagnosed by arthroscopy (21%). Only complete fluid hyperintensity between the posterior horn of the medial meniscus and the capsule was significantly associated with ramp lesions (P value < 0.01). The diagnostic accuracy of this specific sign was moderate, with a specificity of 84%, sensitivity of 75%, PPV of 56%, NPV of 93% and a good level of inter-observer agreement (k = 0.79).

CONCLUSION

The complete fluid filling is the only significant pathological MRI sign for ramp lesions, with moderate accuracy.

Saphenous nerve injury after anterior cruciate ligament reconstruction: Reduced numbness area after ligamentoplasty using quadriceps tendon compared with hamstring tendon

PURPOSE

Injury to the infra-patellar branches of the saphenous nerve (IPBSN) is the main neurological complication of anterior cruciate ligament (ACL) reconstruction procedures. Surgical technique using quadriceps tendon (QT) autograft allows a less invasive tibial approach potentially protecting the IPBSN. The aim of this study was to compare the numbness surface of the cutaneous area supplied by the IPBSN after ACL reconstruction using either hamstring tendon (HT) or QT autografts.

METHODS

This was a retrospective comparative cohort study including 51 patients who underwent ACL reconstruction (27 QT and 24 HT) between January 2017 and April 2018. A sensory clinical evaluation was performed on each patient: length of the tibial scar, eventual numbness surface area and the type of sensory disorder were reported. To be considered as an IPBSN lesion, the numbness area had to spread at least one-centimeter away from the scar.

RESULTS

The average follow-up was 15 months. In the HT group, the numbness area surface measured 21.2 ± 19 cm² (0-77) and the scar length was on average 31.3 ± 5.6 mm. In the QT group, the numbness area was reduced to 5 ± 10 cm² (P = .0007) as well as the scar length (13.3 ± 2.8 mm, P < .0001). We counted five (17.8%) and 19 (76%) real IPBSN lesions in the QT and HT groups, respectively (P = .0002). Hypoesthesia was the main sensory disorder observed (87.5%).

CONCLUSION

Numbness area of the cutaneous surface supplied by the IPBSN after ACL reconstruction is reduced using QT autograft compared with HT autograft.

Which factors influence proximal femoral asymmetry?

Aims

In patients where the proximal femur shows gross deformity due to degenerative changes or fracture, the contralateral femur is often used to perform preoperative templating for hip arthroplasty. However, femurs may not be symmetrical: the aim of this study was to determine the degree of variation between hips in healthy individuals and to determine whether it is affected by demographic parameters.

Materials and Methods

CT-scan based modelling was used to examine the pelvis and bilateral femurs of 345 patients (211 males, 134 women; mean age 62 years (standard deviation (sd) 17), mean body mass index 27 kg/m2 (sd 5)) representing a range of ethnicities. The femoral neck-shaft angle (NSA), femoral offset (FO), femoral neck version (FNV), femoral length (FL), femoral canal flare index (fCFI), and femoral head radius (FHr) were then determined for each patient. All measurements were constructed using algorithm-calculated landmarks, resulting in reproducible and consistent constructs for each specimen. We then analyzed femoral symmetry based on absolute differences (AD) and percentage asymmetry (%AS) following a previously validated method.

Results

We found an asymmetry > 2% for NSA (mean AD 2.9°, mean %AS 2.3; p = 0.03), FO (AD 3.8 mm, %AS 9.1 ; p = 0.01), FNV (AD 5.1°, %AS 46.7 ; p = 0.001) and fCFI (AD 0.2 mm, %AS 5.4 ; p = 0.7). Significant relationships were found for AD regarding NSA and ethnicity (p = 0.037), FL and height (R2 = 0.22), and fCFI and gender (R2 = 0.34).

Conclusion

Our data confirm the presence of asymmetry of proximal femurs, which is mostly independent of demographic parameters. In cases where contralateral templating is used, such asymmetry may lead to inaccurate anatomical restoration of the hip if the templated sizes are routinely implanted. However, the clinical impact cannot be determined from our investigation. Cite this article: Bone Joint J 2018;100-B:839–44.

Anatomical description of the umbilical arteries and impact of their ligation on pelvic and perineal vascular supply after cystectomy in women

OBJECTIVE

In radical cystectomy, the surgeon generally ligates the umbilical artery at its origin. This artery may give rise to several arteries that supply the sexual organs. Our aim was to evaluate pelvic and perineal devascularisation in women after total cystectomy.

PATIENTS AND METHODS

We carried out a prospective anatomical and radiological study. We performed bilateral pelvic dissections of fresh adult female cadavers to identify the dividing branches of the umbilical artery. In parallel, we examined and compared the pre- and postoperative imaging investigations [magnetic resonance imaging (MRI) angiography] in patients undergoing cystectomy for benign disease to quantify the loss of pelvic vascularisation on the postoperative images by identifying the occluded arteries.

RESULTS

The anatomical study together with the radiological study visualised 35 umbilical arteries (n = 70) with their branching patterns and collateral arteries. The uterine artery originated from the umbilical artery in more than 75% of cases (n = 54) of the internal pudendal artery in 34% (n = 24) and the vaginal artery in 43% (n = 30). The postoperative MRI angiograms showed pelvic devascularisation in four patients. Devascularisation was dependent on the level of surgical ligation. In the four patients with loss of pelvic vascular supply, the umbilical artery had been ligated at its origin.

CONCLUSION

The umbilical artery gives rise to various branches that supply the pelvis and perineum. If the surgeon ligates the umbilical artery at its origin during total cystectomy, there is a significant risk of pelvic and perineal devascularisation.

Results of non-operative treatment of olecranon fracture in over 75-year-olds

INTRODUCTION

Surgery is the gold-standard treatment of displaced olecranon fracture, but is associated with numerous complications, especially in the elderly. Functional results of non-operative treatment in this population have never been analyzed in a prospective study.

STUDY HYPOTHESIS

Non-operative treatment of isolated olecranon fracture with stable elbow-joint in over 75-year-olds gives functional results comparable to those of surgery as reported in the literature, with fewer complications.

MATERIAL AND METHODS

A prospective study analyzed functional results of non-operative treatment of isolated closed Mayo I and II olecranon fracture with stable elbow, in patients aged ≥75 years. The principal assessment criterion was functional recovery on the Mayo Elbow Performance Score (MEPS) and QuickDASH at 6 months.

RESULTS

Twenty-two fractures in 21 patients were included. Mean MEPS was 95.26/100 (range, 85-100), and mean QuickDASH 4.3 (range, 0-29.55). Eighteen fractures showed osteoarthritis of the olecranon. There were no cases of elbow instability. There were no complications.

DISCUSSION

Non-operative treatment of olecranon fracture in patients aged ≥75 years provided excellent functional results at 6 months, without associated complications.

TYPE OF STUDY

Single-center prospective observation cohort study.

LEVEL OF EVIDENCE

4.

Radiation dose and magnification in pelvic X-ray: EOS™ imaging system versus plain radiographs

BACKGROUND

In plain pelvic X-ray, magnification makes measurement unreliable. The EOS™ (EOS Imaging, Paris France) imaging system is reputed to reproduce patient anatomy exactly, with a lower radiation dose. This, however, has not been assessed according to patient weight, although both magnification and irradiation are known to vary with weight. We therefore conducted a prospective comparative study, to compare: (1) image magnification and (2) radiation dose between the EOS imaging system and plain X-ray.

HYPOTHESIS

The EOS imaging system reproduces patient anatomy exactly, regardless of weight, unlike plain X-ray.

MATERIAL AND METHOD

A single-center comparative study of plain pelvic X-ray and 2D EOS radiography was performed in 183 patients: 186 arthroplasties; 104 male, 81 female; mean age 61.3±13.7years (range, 24-87years). Magnification and radiation dose (dose-area product [DAP]) were compared between the two systems in 186 hips in patients with a mean body-mass index (BMI) of 27.1±5.3kg/m² (range, 17.6-42.3kg/m²), including 7 with morbid obesity.

RESULTS

Mean magnification was zero using the EOS system, regardless of patient weight, compared to 1.15±0.05 (range, 1-1.32) on plain X-ray (P<10^-5). In patients with BMI<25, mean magnification on plain X-ray was 1.15±0.05 (range, 1-1.25) and, in patients with morbid obesity, 1.22±0.06 (range, 1.18-1.32). The mean radiation dose was 8.19±2.63dGy/cm² (range, 1.77-14.24) with the EOS system, versus 19.38±12.37dGy/cm² (range, 4.77-81.75) with plain X-ray (P<10^-4). For BMI >40, mean radiation dose was 9.36±2.57dGy/cm² (range, 7.4-14.2) with the EOS system, versus 44.76±22.21 (range, 25.2-81.7) with plain X-ray. Radiation dose increased by 0.20dGy with each extra BMI point for the EOS system, versus 0.74dGy for plain X-ray.

CONCLUSION

Magnification did not vary with patient weight using the EOS system, unlike plain X-ray, and radiation dose was 2.5-fold lower.

LEVEL OF EVIDENCE

3, prospective case-control study.

Cryotherapy With Dynamic Intermittent Compression Improves Recovery From Revision Total Knee Arthroplasty

BACKGROUND

The goal of this study was to assess the efficacy of cryotherapy with dynamic intermittent compression (CDIC) in relieving postoperative pain, decreasing blood loss, and improving functional scores after revision total knee arthroplasty (rTKA).

METHODS

We conducted a prospective case-control study (level of evidence: I) to evaluate the efficacy of CDIC on postoperative bleeding, pain, and functional outcomes after rTKA. Forty-three cases were included at a single institution and divided in 2 groups: a control group without CDIC (n = 19) and an experimental group with CDIC (n = 24). Bleeding was evaluated by calculating total blood loss, pain at rest was evaluated with a visual analog scale on postoperative day 3, and function was assessed using the Oxford score at 6 months postoperatively. The comparative analysis was performed using the Fisher exact test.

RESULTS

The CDIC group had significantly lower total blood loss (260 vs 465 mL; P < .05), significantly less pain on day 3 (1 vs 3; P < .05), and a significantly higher functional score (42 vs 40; P < .05) than the control group.

CONCLUSION

This is the first report dealing with the use of CDIC after rTKA. According to our results, it improves the recovery of patients who underwent rTKA; thus, it should be integrated into our daily practice.

Proximal femoral fractures in centenarians. A retrospective analysis of 39 patients

BACKGROUND

A corollary of the current population ageing in France is an increase in proximal femoral fractures (PFFs), particularly among centenarians. The outcomes of PFFs in centenarians in France are unknown. We therefore conducted a retrospective study of centenarians with PFFs both to assess: (1) assess clinical outcomes according to geriatric and trauma scores, (2) and to determine whether routine surgery is warranted.

HYPOTHESIS

Morbidity and mortality in a single-centre cohort of centenarians with surgically treated PFFs are consistent with previous reports.

MATERIAL AND METHOD

We retrospectively reviewed the data of 33 women and 6 men aged 100 years or over who were treated surgically for PFFs at a single-centre between 2008 and 2014. Of the 39 patients, 15 were living at home and 24 in an institution at the time of the injury. Mean (range) values were 3.30 (0-7) for the Parker Mobility Score, 5.84 (0-12) for the Katz index, and 7.46 (2-12) for the Mini Nutritional Assessment (MNA). Mean time from injury to surgery was 1.7 days (0-12). The 26 extra-capsular fractures were managed by internal fixation and the 13 intra-capsular fractures by hip arthroplasty (n=12) or screw fixation (n=1).

RESULTS

After a mean follow-up of 23±14 months (6-60 months), 29 patients had died, including 3 within 48h, 10 within 3 months, and 15 within 1 year. Sequential mortality rates were 33.3% within the first 3 months, 26.9% from months 4 to 9, and 42.2% within the first year. Early dislocation occurred in 3 patients and surgical-site infection in 2 patients. Other complications were heart failure (n=1), confusional state (n=2), pneumonia (n=2), and pyelonephritis (n=2).

DISCUSSION

A PubMed search identified five studies of PFFs in more than 10 centenarians, of which only 2 provided detailed information on postoperative general and local morbidity related to the surgical treatment. Our hypothesis was confirmed for 3-month and 1-year mortality rates, which were at the lower ends of previously reported ranges. Local complications related directly to surgery were considerably more common in our study. PFFs in centenarians carry a high risk of death. Despite the absence of a control group, our data support surgery as the best treatment option.

LEVEL OF EVIDENCE

IV, retrospective study.

Microbial flora on cell-phones in an orthopedic surgery room before and after decontamination

INTRODUCTION

Cell-phones are the typical kind of object brought into the operating room from outside by hospital staff. A great effort is made to reduce the level of potentially contaminating bacteria in the operating room, and introducing these devices may run counter to good practice. The study hypothesis was that cell-phones are colonized by several strains of bacteria and may constitute a source of nosocomial contamination. The main study objective was to screen for bacterial colonies on the surfaces of cell-phones introduced in an orthopedic surgery room. The secondary objective was to assess the efficacy of decontamination.

MATERIAL AND METHOD

Samples were taken from the cell-phones of hospital staff (surgeons, anaesthetists, nurses, radiology operators, and external medical representatives) entering the operating room of the university hospital center orthopedic surgery department, Toulouse (France). Sampling used Count Tact^® contact gel, without wiping the phone down in advance. Both sides of the phone were sampled, before and after decontamination with a pad imbibed with 0.25% Surfanios^® Premium disinfectant. A nasal sample was also taken to investigate the correlation between Staphylococcus aureus in the nasal cavities and on the cell-phone.

RESULTS

Fifty-two cell-phones were sampled. Before decontamination, the mean number of colony-forming units (CFU) was 258 per phone (range, 0-1,664). After decontamination, it was 127 (range, 0-800) (P=0.0001). Forty-nine cell-phones bore CFUs before decontamination (94%), and 39 after (75%) (P=0.02).

DISCUSSION

Cell-phones are CFU carriers and may thus lead to contamination. Guidelines should be drawn up to encourage cleaning phones regularly and to reduce levels of use within the operating room.

Total hip arthroplasty survival in femoral head avascular necrosis versus primary hip osteoarthritis: Case-control study with a mean 10-year follow-up after anatomical cementless metal-on-metal 28-mm replacement

BACKGROUND

Total hip arthroplasty is the most widely used procedure to treat avascular necrosis (AVN) of the femoral head. Few studies have compared the outcomes of THA in femoral head AVN and primary hip osteoarthritis. Therefore we performed a case-control study to compare THA for femoral head AVN vs. primary hip osteoarthritis in terms of: (1) prosthesis survival, (2) complication rates, (3) functional outcomes and radiographic outcomes, (4) and to determine whether specific risk factors for THA failure exist in femoral head AVN.

HYPOTHESIS

THA survival is similar in femoral head AVN and primary hip osteoarthritis.

MATERIAL AND METHODS

We compared two prospective cohorts of patients who underwent THA before 65 years of age, one composed of cases with femoral head AVN and the other of controls with primary hip osteoarthritis. In both cohorts, a cementless metal-on-metal prosthesis with a 28-mm cup and an anatomical stem was used. Exclusion criteria were THA with other types of prosthesis, posttraumatic AVN, and secondary osteoarthritis. With α set at 5%, to obtain 80% power, 246 patients were required in all. Prosthesis survival was assessed based on time to major revision (defined as replacement of at least one implant fixed to bone) and time to aseptic loosening. The other evaluation criteria were complications, Postel-Merle d'Aubigné (PMA) score, and the Engh and Agora Radiographic Assessment (ARA) scores for implant osseointegration.

RESULTS

The study included 282 patients, 149 with AVN and 133 with osteoarthritis. Mean age was 47.8±10.2 years (range, 18.5-65) and mean follow-up was 11.4±2.8 years (range, 4.5-18.3 years). The 10-year survival rates were similar in the two groups: for major revision, AVN group, 92.5% (95% confidence interval [95% CI], 90.2-94.8) and osteoarthritis group, 95.3% (95% CI, 92.9-97.7); for aseptic loosening, AVN group, 98.6% (95% CI, 97.6-98.6) and osteoarthritis, 99.2% (95% CI, 98.4-100). The AVN group had higher numbers of revision for any reason (19 vs. 6, P=0.018) and for dislocation (8 vs. 1, P=0.031). Mean PMA scores at last follow-up were comparable in the AVN group (17.65±1.27 [range, 10-18]) and osteoarthritis group (17.59±1.32 [range, 14-18]) (P=0.139). Osseointegration was also similar in the two groups: global Engh score, 26.51±1.81 (range, 14-27) for AVN and 26.84±0.91 (range, 19.5-27) for osteoarthritis (P=0.065); femoral ARA score, 5.83±0.46 (range, 3-6) for AVN and 5.90±0.42 (range, 3-6) for osteoarthritis (P=0.064); and cup ARA score, 5.74±0.67 (range, 3-6) for AVN and 5.78±0.66 (range, 3-6) for osteoarthritis (P=0.344).

DISCUSSION

Survival in this study was good and consistent with recent data on AVN, with no difference between AVN and osteoarthritis. Revisions for any cause or for dislocation were more common after THA for AVN. Functional outcomes were similar in the AVN and osteoarthritis groups. An anatomical cementless prosthesis combined with metal-on-metal 28-mm bearing provides durable good outcomes.

LEVEL OF EVIDENCE

III, non-randomized comparison of two prospective cohorts.

Is the prognosis the same for periprosthetic joint infections due to Staphylococcus aureus versus coagulase-negative staphylococci? A retrospective study of 101 patients with 2-year minimum follow-up

BACKGROUND

Staphylococcus aureus (SA) and Coagulase-negative staphylococci (CoNS) are often responsible for infections of total hip arthroplasty (THA) and total knee arthroplasty (TKA). One of the main differences between these two microorganisms is their virulence, with SA presumed to be more virulent; however, few studies have specifically investigated the impact of this virulence. This inspired us to carry out a retrospective study to evaluate whether the healing rate differed between SA and CoNS infections.

HYPOTHESIS

We hypothesised that the healing rate is lower for SA prosthetic joint infections.

MATERIALS AND METHODS

This was a retrospective study of 101 consecutive Staphylococcus infection cases that occurred between 2007 and 2011. There were 56 men and 45 women with an average age of 69 years (range 23-95). The infection was associated with TKA in 38 cases and THA in 63 cases. Thirty-two percent of patients had one or more comorbidities with infectious potential. In our cohort, there were 32 SA infections (31.7 %) and 69 CoNS infections (68.3 %) with 58 of the infections being methicillin-resistant (15 SA and 43 CoNS); there were 27 polymicrobial infections (26.7 %).

RESULTS

With a minimum 24-month follow-up after the end of antibiotic treatment, the healing rate was 70.3 % overall (71 patients). The healing rate was 75 % in the SA group (24 patients) versus 68.1 % (47 patients) in the CoNS group (P = 0.42).

CONCLUSION

Our hypothesis was not confirmed: the healing rate of SA prosthetic joint infections was not lower than that of CoNS infections.

LEVEL OF EVIDENCE

III, retrospective case-control study.

Minimally invasive medial hip approach

The medial approach to the hip via the adductors, as described by Ludloff or Ferguson, provides restricted visualization and incurs a risk of neurovascular lesion. We describe a minimally invasive medial hip approach providing broader exposure of extra- and intra-articular elements in a space free of neurovascular structures. With the lower limb in a "frog-leg" position, the skin incision follows the adductor longus for 6cm and then the aponeurosis is incised. A slide plane between all the adductors and the aponeurosis is easily released by blunt dissection, with no interposed neurovascular elements. This gives access to the lesser trochanter, psoas tendon and inferior sides of the femoral neck and head, anterior wall of the acetabulum and labrum. We report a series of 56 cases, with no major complications: this approach allows treatment of iliopsoas muscle lesions and resection or filling of benign tumors of the cervical region and enables intra-articular surgery (arthrolysis, resection of osteophytes or foreign bodies, labral suture).

The frequency of sequelae of slipped upper femoral epiphysis in cam-type femoroacetabular impingement

Slipped upper femoral epiphysis (SUFE) is one of the known causes of cam-type femoroacetabular impingement (FAI). The aim of this study was to determine the proportion of FAI cases considered to be secondary to SUFE-like deformities.

We performed a case–control study on 96 hips (75 patients: mean age 38 years (15.4 to 63.5)) that had been surgically treated for FAI between July 2005 and May 2011. Three independent observers measured the lateral view head–neck index (LVHNI) to detect any SUFE-like deformity on lateral hip radiographs taken in 45° flexion, 45° abduction and 30° external rotation. A control group of 108 healthy hips in 54 patients was included for comparison (mean age 36.5 years (24.3 to 53.9).

The impingement group had a mean LVHNI of 7.6% (16.7% to -2%) versus 3.2% in the control group (10.8% to -3%) (p < 0.001). A total of 42 hips (43.7%) had an index value > 9% in the impingement group versus only six hips (5.5%) in the control group (p < 0.001). The impingement group had a mean α angle of 73.9° (96.2° to 53.4°) versus 48.2° (65° to 37°) in the control group (p < 0.001).

Our results suggest that SUFE is one of the primary aetiological factors for cam-type FAI.

Cite this article: Bone Joint J 2014; 96-B:724–9.

Frequency of radiographic signs of slipped capital femoral epiphysiolysis sequelae in hip arthroplasty candidates for coxarthrosis

INTRODUCTION

The rate of osteoarthritis of the hip secondary to slipped capital femoral epiphysis (SCFE) is a subject of debate, and its frequency is underestimated in particular because of subclinical forms that may not be diagnosed during childhood.

HYPOTHESIS

The frequency of radiographic anomalies subsequent to SCFE in adults requiring hip arthroplasty is higher than that reported in recent studies (6% to 15%).

MATERIALS AND METHODS

A prospective single-center epidemiological radiography study was performed by one observer. Hip X-rays of patients who were being treated by arthroplasty for advanced hip osteoarthritis between January 2010 and May 2012 were analyzed. The etiology of osteoarthritis was classified in each patient according to the data obtained (primary, SCFE, dysplasia, protrusio acetabuli, other). The lateral view head-neck index (LVHNI) was used to quantify posterior translation of the femoral head, and identify SCFE sequelae.

RESULTS

One hundred and eighty-six hips were included. Osteoarthritis was considered primary in 51 patients (27.4%), secondary to dysplasia in 42 (22.5%), protrusio acetabuli in 38 (20.5%) or another disease in nine (4.9%) while 46 hips (24.7%) presented a radiographic image suggesting SCFE past history. SCFE type deformities were the primary etiology of osteoarthritis in patients less than 60years old (30/84 or 35.7%). The mean age of patients in the SCFE group was 56.2years old (26-80) compared to 66 (54-91) for the primary osteoarthritis group (P<0.0001). The mean LVHNI was 13% (9-24%) in the SFCE group, the mean body mass index was 27.1kg/m(2) (±3.5; 18.2-35.4) in the SFCE group and the male to female ratio was 7.3/1.

CONCLUSION

Our study identified a population with a morphological SCFE type anomaly of the coxofemoral joint (LVHNI>9%), which results in the development of earlier osteoarthritis than that found in the rest of the population. SCFE is more common than reported in the literature because it is the first etiology of osteoarthritis of the hip in subjects less than 60years old.

LEVEL OF EVIDENCE

Level III. Diagnostic prospective study with a control group.

Pudendal nerve neuralgia after hip arthroscopy: retrospective study and literature review

INTRODUCTION

Pudendal nerve neurapraxia is a classic complication after traction on the fracture table. Diagnosis, however, is difficult and often overlooked, especially after arthroscopy in traction on fracture table; incidence is therefore not known exactly.

HYPOTHESIS

The study hypothesis was that incidence of pudendal nerve neuropathy exceeds 1% after hip arthroscopy.

MATERIALS AND METHODS

Results for 150 patients (79 female, 71 male) undergoing hip arthroscopy between 2000 and 2010 were analyzed retrospectively. The principal assessment criterion was onset of pudendal neuralgia. Secondary criteria were risk factors (history, surgery time, type of anesthesia), associated complications, onset to diagnosis interval and pattern of evolution.

RESULTS

At a mean 93 months' follow-up, there were 3 cases (2 women, 1 man) (2%) of pure sensory pudendal neuralgia; 2 concerned labral lesion resection and 1 osteochondromatosis. Surgery time ranged from 60 to 120min, under general anesthesia with curarization. Time to diagnosis was 3 weeks. No complementary examinations were performed. Spontaneous resolution occurred at 3 weeks to 6 months. No significant risk factors emerged.

CONCLUSION

The present study found 2% incidence of pudendal neuralgia, with no risk factors emerging from analysis. Prevention involves limiting traction force and duration by using a large pelvic support (diameter>8-10cm). Patient information and postoperative screening should be systematic.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Obesity has no adverse effect on the outcome of unicompartmental knee replacement at a minimum follow-up of seven years

The significance of weight in the indications for unicompartmental knee replacement (UKR) is unclear. Our hypothesis was that weight does not affect the long-term rate of survival of UKRs. We undertook a retrospective study of 212 UKRs at a mean follow-up of 12 years (7 to 22). The patients were distributed according to body mass index (BMI; < vs ≥ 30 kg/m(2)) and weight (< vs ≥ 82 kg). Kaplan-Meier survivorship analysis was performed and ten-year survival rates were compared between the sub-groups. Multimodal regression analysis determined the impact of the various theoretical contraindications on the long-term rate of survival of UKR. The ten-year rates of survival were similar in the two weight subgroups (≥ 82 kg: 93.5% (95% confidence interval (CI) 66.5 to 96.3); < 82 kg: 92.5% (95% CI 82.5 to 94.1)) and also in the two BMI subgroups (≥ 30 kg/m(2): 92% (95% CI 82.5 to 95.3); < 30 kg/m(2): 94% (95% CI 78.4 to 95.9)). Multimodal regression analysis revealed that weight plays a part in reducing the risk of revision with a relative risk of 0.387, although this did not reach statistical significance (p = 0.662). The results relating weight and BMI to the clinical outcome were not statistically significant. Thus, this study confirms that weight does not influence the long-term rate of survival of UKR.

The lateral view head-neck index (LVHNI): a diagnostic tool for the sequelae of slipped capital femoral epiphysis

INTRODUCTION

It is a well-known fact that slipped capital femoral epiphysis (SCFE) is one of the causes of premature hip osteoarthritis and anterior femoroacetabular impingement. But there are no reliable, published diagnostic methods to measure the residual deformity of slipped capital femoral epiphysis. We propose using the lateral view head-neck index (LVHNI) measurement on a specific lateral X-ray view of the hip for this purpose.

HYPOTHESIS

The LVHNI can detect and quantify the posterior translation of the femoral head and this index can be measured reliably.

MATERIALS AND METHODS

A prospective radiography study was performed by three observers. The hip X-rays of patients who were being treated by arthroplasty for hip osteoarthritis (total hip replacement or hip resurfacing) between January 2010 and December 2011 were analyzed. The LVHNI, which quantifies the posterior translation of the femoral head, was measured on a lateral view of the hip in 45° flexion/45° abduction/30° external rotation. The presence of a pistol grip deformity on A/P X-rays was also assessed.

RESULTS

The analysis was performed on 131 hips in 120 patients having an average age of 61 years (range 37-91). The chosen LVHNI threshold of 9% resulted in a sensitivity of 89.1% (95% CI: 78.8%-95.5%) and a specificity of 82.4% (95% CI: 71.2%-89.7%) for detecting the presence of a pistol grip deformity. Twenty percent of the hips with no visible deformity on A/P X-rays had a pathological index value. The inter-observer reproducibility was good for the LHNI [intraclass correlation coefficient (ICC): 0.61; 95% CI: 0.51-0.71] and for detecting a pistol grip deformity (ICC: 0.74; 95% CI: 0.62-0.85). The intra-observer reproducibility was excellent for the LHNI (ICC: 0.78; 95% CI: 0.57-0.88) and the pistol grip deformity (ICC: 0.85; 95% CI: 0.74-0.92).

CONCLUSION

The LVHNI is a reliable and reproducible tool to identify deformities secondary to SCFE on specific lateral femoral neck X-rays. If the index value is greater than 9%, SCFE sequelae may be present. In addition, this study showed that 20% of hips with normal A/P X-rays had a pathological index.

LEVEL OF EVIDENCE

Level IV, prospective diagnostic study without control group.

CT scan does not improve the reproducibility of trochanteric fracture classification: a prospective observational study of 53 cases

INTRODUCTION

The reproducibility of various classification systems for trochanteric fractures is poor. This problem could be related to a lack of readability when using conventional X-rays.

HYPOTHESIS

Computed tomography scanning (CT scan) will improve the interobserver reproducibility of the AO classification for trochanteric fractures.

PATIENTS AND METHODS

This was a prospective, observational, descriptive study following a group of 53 patients with trochanteric fractures. The fractures were evaluated with conventional X-rays, CT scan slices and 3D reconstruction (3DR). The resulting images were blinded and analysed by two observers using two classification systems: AO and Evans modified by Jensen (EVJE). A sample size of 53 was needed to show an improvement in the interobserver reproducibility when deciding the AO classification type with CT scan images. Kappa coefficients were used to measure interobserver reproducibility and agreement; agreement is the degree of consistency in the analysis by one observer who views the same fracture on two different imaging modalities.

RESULTS

The interobserver reproducibility for the AO classification was 0.28 for X-rays, 0.33 for CT scan and 0.28 for 3DR. For the EVJE classification, these coefficients were 0.50 for X-rays, 0.35 for CT scan and 0.47 for 3DR. The agreement rate between the two imaging modalities was between 0.38 and 0.58 for X-rays/CT scan and between 0.79 and 0.86 for CT scan/3DR.

DISCUSSION

The primary objective of this study was not achieved. CT imaging does not improve the interobserver reproducibility of various classification systems for trochanteric fractures. However, by providing images as slices, the complex nature of fractures in this area was revealed. The challenges related to classifying various fractures are not exclusively related to a "readability" problem, but also an understanding and analysis problem.

LEVEL OF EVIDENCE

Prospective diagnostic study, level III.

Surgery for femoroacetabular impingement using a minimally invasive anterolateral approach: analysis of 118 cases at 2.2-year follow-up

INTRODUCTION

Treatment of femoroacetabular impingement (FAI) has progressed over time from using long incisions and dislocation to using arthroscopic surgery. Minimally invasive treatment has rarely been evaluated and a minimally invasive, anterolateral approach has not been used up to now for this indication. A prospective, on-going study was performed to evaluate surgical treatment of FAI with a minimally invasive, anterolateral approach.

HYPOTHESIS

Femoral neck, acetabulum and labrum abnormalities can be corrected without significant morbidity using a minimally invasive, anterolateral approach without dislocation.

PATIENTS AND METHODS

Treatment of 120 FAI cases (108 patients, 16 women, 92 men, 12 bilateral cases during one surgical session), average age: 34 years (18.9-63.5 years), was done prospectively and in an uninterrupted series. Two cases were lost to follow-up; 106 patients (118 FAI cases) were evaluated with a follow-up of at least 1 year. Assessments consisted of the Non-Arthritic Hip Score (NAHS), WOMAC, measurement of internal rotation with 90° flexion and the Nötzli alpha angle on an A/P radiograph in 45° of flexion, 45° abduction and 30° external rotation.

RESULTS

Blood loss averaged 1.2g/dl (range 0.5 to 2.7g/dl) and the average operative time was 44.9 minutes (range 30 to 65). With an average follow-up of 2.2 years (range 12 to 54 months), the NAHS changed by 32.5 points (P<0.0001), internal rotation by 19.0° (P<0.0001) and the alpha angle by -24.9° (P<0.0001). Eight surgical revisions were required (6.8%) (four haematomas, two capsular debridement, two additional procedures on the acetabulum) and these had a good outcome; there were no nerve-related or infection-related complications. Four failures (3.5%) were revised by arthroplasty (two patients experienced residual pain and two patients rapidly progressed to osteoarthritis). Eighteen cases progressed by only one Tönnis stage. Brooker stage II and III ossification were observed in 12 cases (10.2%) but these did not affect the functional score and range of motion improvement.

DISCUSSION

This approach, which can be learned and performed quickly, does not require any specific materials and yields a reliable surgical procedure without major complications. This short-term study, where the central cartilaginous compartment was not explored and the labrum was not sutured, comprised a consecutive, non-selected series of patients (independent of age, weight, osteoarthritis stage) and had encouraging results.

LEVEL OF EVIDENCE

Level III, prospective study, no control group.