Comparison of early outcomes of arthroscopic labral repair or debridement : a study using the UK Non-Arthroplasty Hip Registry dataset.

AIMS: This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum. METHODS: Data on adult patients who underwent arthroscopic labral debridement or repair between 1 January 2012 and 31 July 2019 were extracted from the UK Non-Arthroplasty Hip Registry. Patients who underwent microfracture, osteophyte excision, or a concurrent extra-articular procedure were excluded. The EuroQol five-dimension (EQ-5D) and International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected preoperatively and at six and 12 months post-operatively. Due to concerns over differential questionnaire non-response between the two groups, a combination of random sampling, propensity score matching, and pooled multivariable linear regression models were employed to compare iHOT-12 improvement. RESULTS: A total of 2,025 labral debridements (55%) and 1,659 labral repairs (45%) were identified. Both groups saw significant (p < 0.001) EQ-5D and iHOT-12 gain compared to preoperative scores at 12 months (iHOT-12 improvement: labral repair = +28.7 (95% confidence interval (CI) 26.4 to 30.9), labral debridement = +24.7 (95% CI 22.5 to 27.0)), however there was no significant difference between procedures after multivariable modelling. Overall, 66% of cases achieved the minimum clinically important difference (MCID) and 48% achieved substantial clinical benefit at 12 months. CONCLUSION: Both labral procedures were successful in significantly improving early functional outcome following hip arthroscopy, regardless of age or sex. Labral repair was associated with superior outcomes in univariable analysis, however there was no significant superiority demonstrated in the multivariable model. Level of evidence: III Cite this article: Bone Jt Open 2022;3(4):291-301.

Capsular Mechanics After Periacetabular Osteotomy for Hip Dysplasia.

BACKGROUND: Hip dysplasia is characterized by insufficient acetabular coverage around the femoral head, which leads to instability, pain, and injury. Periacetabular osteotomy (PAO) aims to restore acetabular coverage and function, but its effects on capsular mechanics and joint stability are still unclear. The purpose of this study was to examine the effects of PAO on capsular mechanics and joint range of motion in dysplastic hips. METHODS: Twelve cadaveric dysplastic hips (denuded to bone and capsule) were mounted onto a robotic tester and tested in multiple positions: (1) full extension, (2) neutral 0°, (3) flexion of 30°, (4) flexion of 60°, and (5) flexion of 90°. In each position, the hips underwent internal and external rotation, abduction, and adduction using 5 Nm of torque. Each hip then underwent PAO to reorient the acetabular fragment, preserving the capsular ligaments, and was retested. RESULTS: The PAO reduced internal rotation in flexion of 90° (∆IR = -5°; p = 0.003), and increased external rotation in flexion of 60° (∆ER = +7°; p = 0.001) and flexion of 90° (∆ER = +11°; p = 0.001). The PAO also reduced abduction in extension (∆ABD = -10°; p = 0.002), neutral 0° (∆ABD = -7°; p = 0.001), and flexion of 30° (∆ABD = -8°; p = 0.001), but increased adduction in neutral 0° (∆ADD = +9°; p = 0.001), flexion of 30° (∆ADD = +11°; p = 0.002), and flexion of 60° (∆ADD = +11°; p = 0.003). CONCLUSIONS: PAO caused reductions in hip abduction and internal rotation but greater increases in hip adduction and external rotation. The osseous acetabular structure and capsule both play a role in the balance between joint mobility and stability after PAO.

Cam Osteochondroplasty for Femoroacetabular Impingement Increases Microinstability in Deep Flexion: A Cadaveric Study.

PURPOSE: The purpose of this in vitro cadaveric study was to examine the contributions of each surgical stage during cam femoroacetabular impingement (FAI) surgery (i.e., intact-cam hip, T-capsulotomy, cam resection, and capsular repair) toward hip range of motion, translation, and microinstability. METHODS: Twelve cadaveric cam hips were denuded to the capsule and mounted onto a robotic tester. The hips were positioned in several flexion positions-full extension, neutral (0°), 30° of flexion, and 90° of flexion-and performed internal-external rotations to 5 Nm of torque in each position. The hips underwent a series of surgical stages (T-capsulotomy, cam resection, and capsular repair) and were retested after each stage. Changes in range of motion, translation, and microinstability (overall translation normalized by femoral head radius) were measured after each stage. RESULTS: Regarding range of motion, cam resection increased internal rotation at 90° of flexion (change in internal rotation = +6°, P = .001) but did not affect external rotation. Capsular repair restrained external rotation compared with the cam resection stage (change in external rotation = -8° to -4°, P ≤ .04). In terms of translation, the hip translated after cam resection at 90° of flexion in the medial-lateral plane (change in translation = +1.9 mm, P = .04) relative to the intact and capsulotomy stages. Regarding microinstability, capsulotomy increased microinstability in 30° of flexion (change in microinstability [ΔM] = +0.05, P = .003), but microinstability did not further increase after cam resection. At 90° of flexion, microinstability did not increase after capsulotomy (ΔM = +0.03, P = .2) but substantially increased after cam resection (ΔM = +0.08, P = .03), accounting for a 31% change with respect to the intact stage. CONCLUSIONS: Cam resection increased microinstability by 31% during deep hip flexion relative to the intact hip. This finding suggests that iatrogenic microinstability may be due to separation of the labral seal and resected contour of the femoral head. CLINICAL RELEVANCE: Our in vitro study showed that, at time zero and prior to postoperative recovery, excessive motion after cam resection could disrupt the labral seal. Complete cam resection should be performed cautiously to avoid disruption of the labral seal and postoperative microinstability.

The impact of mental health disorders on outcomes following hip arthroscopy for femoroacetabular impingement syndrome: a systematic review.

Hip arthroscopy for femoroacetabular impingement syndrome (FAI) has been shown to be beneficial in the short- to medium-term though outcomes vary between individuals. Multiple factors have been suggested to affect outcomes including pre-operative mental health disorders. We undertook a systematic review to assess the evidence relating to the effect of pre-existing mental health disorders on the outcomes following hip arthroscopy for FAI. Following PRISMA guidelines, a multi-database search was undertaken using three key concepts: 'mental health', 'FAI' and 'hip arthroscopy'. Results were screened and data extracted from relevant studies. A total of six studies met the inclusion criteria including 2248 hips, all published between 2017 and 2019. All studies were of evidence level III or IV with reasonable methodological quality. One study demonstrated pre-operative depression to be related to altered pain reduction in the short-term following surgery. Three studies reported inferior outcomes in the medium-term (1-2 years) in those with worse mental health. One study demonstrated an increased risk of persistent pain 2 years following surgery and one a reduced chance of returning to active military service following surgery in those with worse mental health. Despite inferior outcomes individuals with mental health disorders did still benefit from surgery in general. In conclusion, the presence of pre-existing poor mental health is associated with inferior outcomes in the medium-term following arthroscopic surgery for FAI. Surgeons should consider screening patients for mental health disorders before surgery and counselling them appropriately as to the potential for less satisfactory surgical outcomes.

Periacetabular Osteotomy for Developmental Dysplasia of the Hip and Femoroacetabular Impingement: A Study Using the U.K. Non-Arthroplasty Hip Registry (NAHR) Data Set.

BACKGROUND: Periacetabular osteotomy (PAO) is a well-recognized procedure for the treatment of hip dysplasia in young adults and can be used for the surgical management of femoroacetabular impingement (FAI) with acetabular retroversion. The aim of this study was to use a national database to assess the outcomes of PAO for developmental dysplasia of the hip (DDH) and for FAI. METHODS: All patients in whom an isolated PAO had been performed between January 2012 and February 2019 were identified in the Non-Arthroplasty Hip Registry (NAHR). Their outcomes were assessed using the EuroQol-5 Dimensions (EQ-5D) index and the International Hip Outcome Tool (iHOT)-12 preoperatively and then at 6 months, 12 months, and 2 years postoperatively. RESULTS: Six hundred and thirty (630) PAOs were identified, with 558 (89%) performed for DDH and 72 (11%) performed for FAI. Most patients (90%) were female. The mean age in the DDH group (31.2 years) was significantly higher (p < 0.0001) than that in the FAI group (26.5 years). There were no other significant between-group demographic differences. Preoperatively and at each follow-up time-period, iHOT-12 scores were better in the DDH group than in the FAI group; however, only the preoperative scores differed significantly. There was significant improvement between the preoperative and 6-month iHOT-12 and EQ-5D index scores in both the DDH and the FAI group. This improvement was maintained at 12 months postoperatively, by which time almost 90% of the patients had achieved the minimum clinically important difference (MCID) in their iHOT-12 score. CONCLUSIONS: This study shows that PAO is a successful surgical intervention for DDH and FAI in the short term, with significant improvement in patient-reported outcome scores that is maintained up to 2 years postoperatively. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Hip Joint Torsional Loading Before and After Cam Femoroacetabular Impingement Surgery.

BACKGROUND: Surgical management of cam femoroacetabular impingement (FAI) aims to preserve the native hip and restore joint function, although it is unclear how the capsulotomy, cam deformity, and capsular repair influence joint mechanics to balance functional mobility. PURPOSE: To examine the contributions of the capsule and cam deformity to hip joint mechanics. Using in vitro, cadaveric methods, we examined the individual effects of the surgical capsulotomy, cam resection, and capsular repair on passive range of motion and resistance of applied torque. STUDY DESIGN: Descriptive laboratory study. METHODS: Twelve cadaveric hips with cam deformities were skeletonized to the capsule and mounted onto a robotic testing platform. The robot positioned each intact hip in multiple testing positions: (1) extension, (2) neutral 0°, (3) flexion 30°, (4) flexion 90°, (5) flexion-adduction and internal rotation (FADIR), and (6) flexion-abduction and external rotation. Then the robot performed applicable internal and external rotations, recording the neutral path of motion until a 5-N·m of torque was reached in each rotational direction. Each hip then underwent a series of surgical stages (T-capsulotomy, cam resection, capsular repair) and was retested to reach 5 N·m of internal and external torque again after each stage. During the capsulotomy and cam resection stages, the initial intact hip's recorded path of motion was replayed to measure changes in resisted torque. RESULTS: Regarding changes in motion, external rotation increased substantially after capsulotomies, but internal rotation only further increased at flexion 90° (change +32%, P = .001, d = 0.58) and FADIR (change +33%, P < .001, d = 0.51) after cam resections. Capsular repair provided marginal restraint for internal rotation but restrained the external rotation compared with the capsulotomy stage. Regarding changes in torque, both internal and external torque resistance decreased after capsulotomy. Compared with the capsulotomy stage, cam resection further reduced internal torque resistance during flexion 90° (change -45%, P < .001, d = 0.98) and FADIR (change -37%, P = .003, d = 1.0), where the cam deformity accounted for 21% of the intact hip's torsional resistance in flexion 90° and 27% in FADIR. CONCLUSION: Although the capsule played a predominant role in joint constraint, the cam deformity provided 21% to 27% of the intact hip's resistance to torsional load in flexion and internal rotation. Resecting the cam deformity would remove this loading on the chondrolabral junction. CLINICAL RELEVANCE: These findings are the first to quantify the contribution of the cam deformity to resisting hip joint torsional loads and thus quantify the reduced loading on the chondrolabral complex that can be achieved after cam resection.

Current practice of BHS members in the treatment of osteonecrosis of the femoral head in adults.

INTRODUCTION: The management of osteonecrosis (ON) of the femoral head remains controversial. It is unclear the extent to which non-arthroplasty procedures are used and there has been no previous report of the trends in operative management of ON in the UK. Our objective is to report current trends in management of ON of the femoral head amongst specialist hip surgeons in the UK. METHODS: A single-stage internet-based survey was e-mailed to 352 eligible members of the British Hip Society (BHS). This consisted of 10 question stems including 16 hypothetical clinical scenarios with imaging. RESULTS: 115 active Consultant members of the BHS completed the survey. For symptomatic pre-collapse ON we found core decompression (CD) was the most common operative intervention and for post-collapse ON we found that total hip arthroplasty (THA) was the most common operative intervention. We found no difference in the rate of operative intervention between 24 and 48-year-old patients at any stage of ON but joint preserving procedures were more often selected for the younger patient and arthroplasty for the older patient. Surgeons were more likely to offer arthroplasty to a 48-year-old patient at an earlier stage of disease. CONCLUSIONS: Our respondents would offer different operative interventions dependent on stage of ON and patient age. Core decompression (CD) and arthroplasty were common but variation in treatment options offered suggests a lack of consensus amongst UK hip surgeons. We suggest that further research such as a prospective RCT is needed to gain consensus on management of this condition.

Experience and outcome data of the British non-arthroplasty hip registry.

INTRODUCTION: The non-arthroplasty hip registry (NAHR) is a United Kingdom national register that monitors the efficacy of hip preservation surgery. We aim to highlight early experiences of incorporating the NAHR into our practice at a tertiary centre. METHODS: Between December 2013 and February 2015, 381 patients were identified on the NAHR database that had undergone non-arthroplasty hip surgery. Patient-related outcome measures EuroQuol 5D-5L (EQ-5D) and the International Hip Outcome Tool 12 (iHOT-12) were recorded at baseline and 6 months. RESULTS: The 289 arthroscopic surgeries showed a statistical significant difference (p<0.05) in iHOT-12 for both males (45.21-65.07) and females (34.57 to 55.53), and in EQ-5D for both males (0.59-0.75) and females (0.56-0.65). The 92 open procedures showed a statistical significant difference (p<0.05) in both iHOT-12 (31.71-62.42) and EQ-5D (0.54-0.68). CONCLUSIONS: Overall our results from the NAHR indicate hip preservation surgery is effective at relieving pain and improving quality of life in the short term.

Three-dimensional assessment of impingement risk in geometrically parameterised hips compared with clinical measures.

Abnormal bony morphology is a factor implicated in hip joint soft tissue damage and an increased lifetime risk of osteoarthritis. Standard 2-dimensional radiographic measurements for diagnosis of hip deformities, such as cam deformities on the femoral neck, do not capture the full joint geometry and are not indicative of symptomatic damage. In this study, a 3-dimensional geometric parameterisation system was developed to capture key variations in the femur and acetabulum of subjects with clinically diagnosed cam deformity. The parameterisation was performed for computed tomography scans of 20 patients (10 female and 10 male). Novel quantitative measures of cam deformity were taken and used to assess differences in morphological deformities between males and females. The parametric surfaces matched the more detailed, segmented hip bone geometry with low fitting error. The quantitative severity measures captured both the size and the position of cams and distinguished between cam and control femurs. The precision of the measures was sufficient to identify differences between subjects that could not be seen with the sole use of 2-dimensional imaging. In particular, cams were found to be more superiorly located in males than in females. As well as providing a means to distinguish between subjects more clearly, the new geometric hip parameterisation facilitates the flexible and rapid generation of a range of realistic hip geometries including cams. When combined with material property models, these stratified cam shapes can be used for further assessment of the effect of the geometric variation under impingement conditions.

Functional outcomes of total hip arthroplasty in patients aged 30 years or less: a systematic review and meta-analysis.

INTRODUCTION: Young adult hip surgery is a growing subspecialty. Increasingly total hip arthroplasty (THA) is offered to patients aged 30 or less suffering from end-stage hip arthropathy from a variety of congenital, developmental and acquired conditions. There is a paucity of evidence to advise such patients and surgeons alike on the functional outcomes of THA in this age group, as individual studies tend to include small cohorts. METHODS: A systematic review and meta-analysis was performed to assess whether THA in patients aged 30 years or less provides significant functional improvement. The primary outcome measure was change in Harris Hip Score. Secondary outcome measures were implant survivorship and the effect of fixation type and bearing surface. RESULTS: The results of 743 primary THA procedures were included. Weighted mean patient age was 22.7 years. Harris Hip Score improved by a weighted mean difference of 42.17 points out of 100 (95% confidence interval, 36.48-47.86 points, p<0.001) after THA at a weighted mean follow-up of 8.4 years. Pooled revision rate was 5.0% for the same time period. CONCLUSIONS: This is the largest review to date of THA in patients aged 30 or less. The results show significant functional improvement measured by Harris Hip Score. The revision rate of 5% at 8.4 years is comparable to the general THA population. This contrasts high revision rates reported in older reviews of the literature, suggesting adoption of improved techniques and implants in the more recent literature.

A pain in the backside: a case report of coxa saltans occurring at the proximal hamstring origin.

Coxa saltans occurring at the proximal hamstring origin has been rarely reported in the literature. It is better known as occurring at the iliotibial band or the iliopsoas tendon. We report a case of coxa saltans due to subluxation of the origin of the long head of biceps femoris tendon at the ischial tuberosity. This was successfully treated using a mini-open surgical technique. Six weeks postoperatively, the snapping and the associated pain were abolished and the patient was able to resume their participation in athletic activities.

Systematic review of total hip arthroplasty in patients under 30 years old.

We performed a systematic review to assess whether joint replacement in this very young patient group provides significant functional improvement and whether these procedures are associated with good implant survivorship. The studies included presented the results of 450 THA procedures. All patients showed an improvement in functional score and symptom relief. Uncemented stems showed good integration with no signs of loosening. Cemented implants showed high rates of loosening. This study shows that THA in the very young patient can provide good functional improvement and relief of symptoms and that the more modern uncemented implant designs used with hard-on-hard bearings can be associated with improved implant survival. Long-term studies are necessary to confirm the superiority and improved survivorship of these newer implants.

Hip arthrodesis with the dynamic hip screw.

The authors report a series of 10 patients (4 male, 6 female) with end-stage hip degeneration who underwent unilateral hip arthrodesis at an average age of 19 years (range 14-35). Surgery was performed with the patient in the supine position through a Watson-Jones approach and fixation was stabilized with the AO Dynamic Hip Screw (DHS). After surgery, patients were mobilized in a short hip spica. Stable fixation with the DHS could not be achieved at surgery in one patient. Bony union was achieved in seven of the nine patients (78%) with a DHS after an average of 17 weeks (range 9-34). In one patient a painful nonunion developed; it was converted to a total hip arthroplasty 23 months later. Another patient obtained a painless pseudarthrosis, for which no further surgery is planned. The DHS provides a satisfactory means of stabilizing a hip arthrodesis when combined with a hip spica. This method of arthrodesis does not violate the origin or insertion of the abductor mechanism, thereby facilitating future conversion to total hip arthroplasty.