Introduction

Open and arthroscopic hip debridement may be used for treatment of femoral acetabular impingement (FAI). There is a paucity of evidence regarding the efficacy of one over the other.

Introduction

Open hip debridement surgery has been used for treatment of femoral acetabular impingement pain for over ten years in our unit. While literature has reported promising short term outcomes, longer term outcomes are more sparsely reported. We aim to assess survivorship and functional outcome at ten years, in patients who have undergone open hip debridement.

The Ganz trochanteric flip osteotomy has gained popularity in recent years as a surgical approach that can be used when performing debridement surgery and hip resurfacing. The advantages include preservation of blood supply to the femoral head, maintenance of abductor strength and exposure. Morbidity associated with the trochanteric osteotomy is however a problem.

We reviewed the complications associated with the trochanteric flip in 367 patients that had undergone hip resurfacing arthroplasty. Pain, either felt deep within the groin or from prominent screws heads laterally was a significant problem for 96 patients (26.1%) and necessitated screw removal under general anaesthesia at a mean time of 16 months postop. Of these, 14 patients (14.5%) continued to have pain, with 8 patients proceeding to revision surgery; 5 for refractory pain, 1 for aseptic loosening, 1 for aseptic lymphocyte dominated vasculitis associated lesion (ALVAL) and 1 for acetabular soft tissue impingement.

Trochanteric non-union, leading to further surgery, was diagnosed in 24 patients (6.5%) whom underwent reattachment at a mean time of 6 months postop. Within this group the majority of patients were male (16), with a mean age of 53.5 years (range 35 to 65). Trochanteric non-union was associated with smoking, diabetes, obesity, age and non-compliance. Following reattachment surgery, all patients went on to union.

In total 120 patients experienced complications associated with the trochanteric osteotomy that resulted in a need for further surgery, a re-operation rate of 32.6%. Pain from trochanteric screws appears to be the over whelming issue. Surgeons using the trochanteric flip should be aware of the morbidity associated with the approach and counsel patients accordingly pre-operatively. Patients presenting with ongoing pain following screw removal should be investigated extensively for serious underlying problems.

Heterotopic ossification is a recognised complication of surgery on the hip joint that can adversely affect the outcome. The aim of this study was to determine the incidence of heterotopic ossification following surgical hip dislocation and debridement for femoro-acetabular impingement using Ganz trochanteric flip osteotomy approach. We also compared the incidence of heterotopic ossification between two subgroups of patients; in the first group, a shaver burr was used to reshape the femoral head and in the second group, an osteotome was used.

Methods: We reviewed postoperative radiographs of all patients who underwent surgical hip dislocation and debridement during the period between March 2003 and July 2007. We excluded patients with radiographic follow-up of less than one year. Brooker classification was used to grade heterotopic ossifications.

Results: Ninety eight patients (mean age 35 years, range 12–65 years) were included with a mean radiological follow-up of 23 months (range 12–61 months). The overall incidence of heterotopic ossification was 31%. None of the patients developed Brooker grade III or IV heterotopic ossifications. The incidence of heterotopic ossifications in the shaver burr group (n=57) and in the osteotome group (n=41) was 30% and 32%, respectively.

Conclusions: Heterotopic ossification of minor grade is a common complication of surgical hip dislocation using trochanteric flip osteotomy approach. The use of a shaver burr did not result in higher rates of heterotopic ossifications despite the formation of large amounts bone debris.

The aim of Femoro-Acetabular Impingement (FAI) surgery is to improve femoral head-neck clearance by resection of the osseous bump deformity. The purpose of this study was to investigate whether osseous bumps will re-grow and to compare two instruments used for resection osteoplasty; a shaver burr and an osteotome.

We reviewed records of patients who underwent surgical hip dislocation and debridement via Ganz flip osteotomy between March 2003 and July 2007. We excluded patients with less than one-year radiographic follow-up.

Ninety-five patients (95) underwent 98 surgical hip dislocations and were included (mean radiological follow-up 23 months, range 12–61 months). Bump re-growth occurred in 16 cases (16%). Pre and postoperative Non-Arthritic Hip Scores (NAHS) were available for 12 of the 16 patients. The mean pre- and postoperative NAHS were 62 (range 26–95) and 83 (range 41–104) respectively (p= 0.02). In the shaver burr group (n=57), there were 6 cases of bump re-growth (12%) compared to 10 cases in the osteotome group (n=41) (32%).

In this study, recurrence of osseous bumps did not affect the outcome. Using shaver burrs resulted in lower rates of bump re-growth than using osteotomes. This could be related to heat osteonecrosis at the femoral head-neck junction.

We report a 10% failure rate for aseptic loosening and overall revision rate of 15% at 5 years mean follow up in 190 patients using the Cormet 2000 Dual coat ace-tabular component.

Between April 2001 and March 2004, this cup was used in our region by 4 surgeons. It was peripherally expanded and comprised a cobalt chrome shell, plasma sprayed with a further layer of cobalt chrome which was then coated with hydroxyapatite. This backing has since been abandoned in favour of a titanium plasma coat beneath the hydroxyapatite because of a higher than expected incidence of early loosening.

There were 190 cups implanted in 174 patients, 142 with resurfacing heads. The average age was 54 and 99 were male.

Revision for aseptic loosening was required in 20 cups (10%) at a mean interval of 23 months including five within 2 months, Of the early revisions three developed a deep infection. Undiagnosed groin pain in four further patients appeared at revision to arise from an inflamed bursa secondary to impingement of psoas tendon on the rim of the cup. There was one primary infection, one infection following revision of a trochanteric osteotomy and two neck fractures. Persistent unexplained groin pain was seen in three patients who have declined further surgery

Failure of this backing to integrate with bone led to an unacceptably high early loosening rate. Positioning of the larger resurfacing cups is critical to avoid painful irritation of psoas. Early revision carries a high risk of infection.

Between January 2003 and December 2004, 14 patients underwent bilateral resurfacing arthroplasty via a Ganz trochanteric osteotomy. This bilateral group was mobilised fully weight-bearing with crutches. During the same period 139 Ganz trochanteric osteotomies were performed for unilateral hip resurfacing. These patients were mobilised with crutches, weight-bearing up to 10 kg on the operated leg.

Nine osteotomies (32%) in the bilateral group subsequently developed a symptomatic non union requiring revision of fixation. This compares with 10 patients (7%) in the unilateral group. Applying the Fisher’s exact test, the difference reached significance (p=0.0004). In 2 patients a second revision was required to achieve union. In 1 patient, revision of trochanteric fixation precipitated a deep infection.

Protected weight-bearing following a Ganz trochanteric osteotomy is important to the success of the procedure. Simultaneous bilateral hip arthroplasty through a Ganz approach should be avoided. If it is undertaken, we recommend that patients should be non weight-bearing for 6 weeks following surgery. Non union following a Ganz trochanteric osteotomy for arthroplasty carries a significant morbidity.

Since 2003 we have adopted an aggressive approach to the management of slipped upper femoral epiphysis (SUFE) deformity, an important cause of femoro-acetabular impingement and associated with the development of early adult hip arthritis.

Sixteen patients aged 16.7 years (range 11–20), 13 male, have undergone surgery to manage their SUFE deformity. Nine underwent primary surgery using a Ganz approach (7) or in-situ pinning with femoral neck resection via a Smith-Peterson approach (2). Seven had previously undergone in-situ pinning 26 months earlier (range 4–44 months) of whom two had acetabular chondral flap tears with eburnated bone and six had significant labral degenerative changes associated with calcification or tears. Only one of the nine patients who underwent primary aggressive management of their SUFE, had a labral tear. Four patients underwent mobilisation of the femoral head on its vascular pedicle, followed by anatomical realignment.

At an average follow-up of 22.3 months (range 1–41 months) 15 remained well with excellent function. Leg lengths remained equal in 12, with average shortening of 2 cm in the remaining four. Segmental AVN occurred in the first patient after damage to the vascular pedicle during drilling of the neck; the technique has been modified to prevent this.

Despite having performed over 400 surgical hip dislocations, the authors continue to find the management of this condition challenging; nevertheless, having seen the consequences of femoro-acetabular impingement in these young patients, we believe that aggressive management to correct anatomical alignment is essential for the future well being of the hip.

Introduction: Femoroacetabular impingement (FAI) causes pain in young adults and osteoarthritis. Genetic factors are important in the aetiology of osteoarthritis. We aimed to investigate the extent to which FAI has an underlying genetic basis, by studying the siblings of patients undergoing surgery for FAI and comparing them with controls.

Methods: 66 patients (probands, 29 male, 37 female, mean age 39.1 years) treated surgically for FAI provided siblings for the study. Probands were classified as having cam, pincer or mixed FAI. 101 siblings (55 male, 56 female, mean age 38.2 years) were recruited. The control group consisted of their 77 partners and was age and gender-matched. All subjects were assessed clinically and radiologically (standardised AP Pelvic and cross-table lateral radiographs of each hip). Radiographs were scored for the presence of osteoarthritis, and morphological abnormalities.

Participants were classified as:

Normal morphology, no clinical features

Results: The sibling relative risks were significant for groups b, c, and d (ranging between 2–5, p< 0.01). Pro-bands and siblings shared the same pattern of abnormal morphology. Gender specificity was apparent: pincer abnormalities common in sisters but not in brothers. The brothers of probands with cam deformities almost universally demonstrated the same deformity, but only 50% of sisters did.

Discussion: Genetic influences are important in the aetiology of FAI. Whether the morphological abnormality is determined at conception or by an inherited predisposition to an acquired event during development warrants further study. Symptoms are variable, indicating a spectrum of disease progression. These cohorts present an opportunity to prospectively study the natural history of the condition, improve understanding of the mechanisms and pathology, and potentially to be recruited into clinical trials.

Introduction: The open treatment of hip impingement is now a well-recognised technique with numerous publications about pathogenesis and surgical technique. There are very few publications of very small series discussing surgical results.

We present the results of 148 hips at a mean follow-up of 20 months (range 4 – 55).

Methods: This is a two surgeon series of sequential patients including the early learning curve. Patients were treated for impingement through a Ganz trochanteric osteotomy and open surgical hip dislocation. Patient data, operative findings and methods, complication and clinical follow up were recorded as a prospective audit and include Oxford and McCarthy Non Arthritic Hip scores.

Results: The patient demographics are as follows:

141 patients, 148 hips.

We have had the following complications: 4 trochanteric non unions requiring revision fixation, 2 deep vein thrombosis, 2 haematomas, 1 superficial infection, no deep Infections.

Life table survival curve with revision to arthroplasty defined as failure.

Discussion: The early to midterm results of this innovative procedure are encouraging even when including the decision making and surgical technique learning curves. We will present the hip scores and discuss the failures in detail to warn others embarking on this surgery which cases are more likely to lead to unsatisfactory outcomes.

Since 2003 we have adopted an aggressive approach to the management of the SUFE deformity, an important cause of anterior femoro-acetabular impingement, associated with the development of early adult hip arthritis.

16 patients aged 16.7 years (range 11–20, 3 female, 13 male, 8 right, 8 left hips) underwent surgery to manage their SUFE deformity.

7 patients had secondary correction of deformity after previous in-situ pinning and 9 underwent primary surgical management using a Ganz approach (7) or primary in-situ pinning with femoral neck resection via a Smith-Peterson approach (2).

Of the 7 patients who had primary in-situ pinning 26 months (range 4–44 months) earlier, 2 had acetabular chondral flap tears with eburnated bone and 6 had significant labral degenerative changes associated with calcification or tears.

Only one of the nine patients who underwent primary aggressive management of their SUFE, had a labral tear.

4 patients underwent mobilisation of the femoral head on its vascular pedicle followed by anatomical realignment.

At an average follow-up of 22.3 months (range 1–41 months) 15 remained well with excellent function. Leg lengths remained equal in 12, with an average shortening of 2cm in the remaining 4 patients.

Segmental AVN occurred in the first patient after damage to the vascular pedicle during drilling of the neck; the technique has been modified to prevent further occurrences.

Removal of the trochanteric osteotomy screws has been performed in 4 cases.

Despite having performed over 400 surgical hip dislocation, the authors continue to find the management of this condition challenging; nevertheless, having seen the direct consequences of femoro-acetabular impingement at an early stage in these young patients, we believe that aggressive management to correct anatomical alignment is essential for the future well being of the hip.

Thinning of the femoral neck occurs in 77% of patients undergoing hybrid Birmingham hip resurfacing using a posterior approach (Shimmin 2007). Villar recently reported lower neck thinning rates in uncemented Cormet resurfacings (11.7%) compared with hybrid Birmingham resurfacing (13.4%), both via a posterior approach.

We have evaluated implant position and femoral neck thinning in a cohort of 273 uncemented HA coated Cormet 2000 hip resurfacings using ‘B’-series (Titanium/HA coated) cups in 269 patients (mean age 54 years, 39% female) with a mean follow-up of 3 years (range 1–4 years).

Mean cup inclination was 45° (30°–63°), mean SSA 138° (120°–178°). No lucent or sclerotic zones have been identified around the stem of the component. Only one femoral neck fracture has occurred (incidence 0.36%)

We have identified only one case of femoral neck thinning in our series (0.36%).

Whilst Villar has demonstrated a slight reduction in neck thinning rates using the same implants compared to a hybrid fixation Birmingham resurfacing, his neck thinning rates are almost 40 times higher than in our series. Shimmins ‘severe neck thinning (> 10%) rates (27%) are approximately 120 times higher than our series. In addition, we have been unable to confirm the relationship between implant position and neck thinning described by Shimmin in our series using the combined Ganz/uncemented resurfacings compared with Birmingham resurfacings.

Implant design and surgical approach have an impact on ‘neck thinning after resurfacing; we should be wary of treating all resurfacing implants and techniques as a uniform cohort.