Aims. Rotational acetabular osteotomy (RAO) is an effective joint-preserving surgical treatment for acetabular dysplasia. The purpose of this study was to investigate changes in muscle strength, gait speed, and clinical outcome in the operated hip after RAO over a one-year period using a standard protocol for rehabilitation. Patients and Methods. A total of 57 patients underwent RAO for acetabular dysplasia. Changes in muscle strength of the operated hip, 10 m gait speed, Japanese Orthopaedic Association (JOA) hip score, and factors correlated with hip muscle strength after RAO were retrospectively analyzed. Results. Three months postoperatively, the strength of the operated hip in flexion and abduction and gait speed had decreased from their preoperative levels. After six months, the strength of flexion and abduction had recovered to their preoperative level, as had gait speed. At one-year follow-up, significant improvements were seen in the strength of hip abduction and gait speed, but muscle strength in hip flexion remained at the preoperative level. The mean JOA score for hip function was 91.4 (51 to 100)) at one-year follow-up. Body mass index (BMI) showed a negative correlation with both strength of hip flexion (r = -0.4203) and abduction (r = -0.4589) one year after RAO. Although weak negative correlations were detected between strength of hip flexion one year after surgery and age (r = -0.2755) and centre-edge (CE) angle (r = -0.2989), no correlation was found between the strength of abduction and age and radiological evaluations of CE angle and acetabular roof obliquity (ARO). Conclusion. Hip muscle strength and gait speed had recovered to their preoperative levels six months after RAO. The clinical outcome at one year was excellent, although the strength of hip flexion did not improve to the same degree as that of hip abduction and gait speed. A higher BMI may result in poorer recovery of hip muscle strength after RAO. Radiologically, acetabular coverage did not affect the recovery of hip muscle strength at one year’s follow-up. A more intensive rehabilitation programme may improve this. Cite this article: Bone Joint J 2019;101-B:1459–1463

The jackaling position within rugby has not been previously described as a mechanism for proximal hamstring injuries. This prospective single surgeon study included 54 professional rugby players (mean age 26 ± 4.8 years) undergoing acute primary surgical repair of complete, proximal hamstring avulsion injuries confirmed on preoperative magnetic resonance imaging. All study patients underwent a standardised postoperative rehabilitation programme. Predefined outcomes were recorded at regular intervals. Mean follow-up time was 17 months (range, 12 months to 24 months) from date of surgery. 51 patients (94.4%) returned to their pre-injury level of sporting activity. Mean time from surgical repair to full sporting activity was 7 months (range, 4 months to 12 months). Zero patients had recurrence of the primary injury. At 1 year after surgery compared to 3 months after surgery, patients had increased mean isometric hamstring muscle strength at 0° (98.4 ± 2.8% vs 88.1% ± 5.4%, p<0.001), 15° (95.9 ± 2.9 vs 88.2 ± 8.1%, p<0.001) and 45° (92.9% ± 4.1% vs 76.8% ± 9.7%, p<0.001), higher mean lower extremity functional scores (77.0 ± 2.3 vs 64.5 ± 4.5, p<0.001), and improved Marx activity rating scores (14.3 ± 1.5 vs 10.7 ± 2.6, p<0.001). Acute surgical repair of proximal hamstring avulsion injuries caused by the contact jackaling position produces high patient satisfaction, high return to preinjury level of sporting activity, with low risk of recurrence at short-term follow-up

Introduction. Femoroacetabular impingement (FAI) is a morphological hip joint deformity associated with pain and early degenerative changes. Cam-type FAI is prevalent in young male athletes. While biomechanical deficiencies (decreased hip muscle strength and range of motion (ROM)) have been associated with symptomatic cam-type FAI (sFAI), results have been conflicting and little is known about biomechanical characteristics during dynamic tasks. Objectives. (1) Compare coronal-plane hip muscle strength, activation and joint rotation during movement tasks in sFAI hips against healthy controls. (2) Investigate the effect of hip internal rotation ROM (IR-ROM) on these outcomes. Methods. 11 sFAI and 24 well-matched healthy control hips from 18 young adult male athletes were recruited (Table.1). Passive hip IR-ROM was measured with goniometry. Weight-normalised hip abductor and adductor isometric maximal voluntary contraction torques were quantified with handheld dynamometry. Gluteus medius and adductor longus activation and hip coronal-plane kinematics were collected with surface electromyography (EMG) and motion-capture during time-defined phases of sit-to-stand (Fig.1) and single-leg-squat (Fig.2) tasks. Effect of sFAI with hip IR-ROM as a separate independent variable was calculated with 1-way MANCOVA. Results. sFAI had significantly less IR-ROM (19.25°±5.94) than controls (28.83°±7.24) (p<0.001). During the sit-to-stand ascent phase, significantly more hip abduction (F=4.93, p=0.03) was observed in sFAI (13.06°±3.16) compared to controls (10.16°±3.72). With IR-ROM differences controlled for, significantly higher gluteus medius:adductor longus EMG activation ratio (F=4.32, p=0.046) was observed in the same phase in sFAI (0.16±0.34) compared to controls (−0.11±0.31). No other significant results were found. Conclusion. sFAI hips demonstrate altered muscle activation and movement patterns when ascending from seated positions compared to controls, with reduced hip IR-ROM in sFAI hips influencing findings. Abductor and adductor function imbalance may explain why sFAI increases risk of early degenerative changes. Despite study limitations (no imaging for sFAI diagnosis), these findings should be considered when optimising rehabilitation in this population. For any figures and tables, please contact the authors directly

We compared two methods of reconstruction of the abductor mechanism in 15 patients after prosthetic replacement of the upper femur, to assess abductor strength and function. Six patients in group I had direct fixation of the gluteus medius tendon and a segment of the original bone to the prosthesis. Nine patients in group 2 had the abductor tendon fixed to the iliotibial band. We assessed clinical function, isometric muscle strength and muscle cross-sectional area for each patient. The patients in group 1 had better clinical and functional results (p = 0.059), with average peak torques for hip abduction of 92% of that in the non-operated leg in group 1, and of 57% in group 2. Group 1 had a mean muscle cross-sectional area of 69% and a mean value of strength per cross-sectional area of 134% when compared with the control side. The respective values for group 2 were 52% and 91%. Direct fixation of the abductor muscles to the prostheses gave improved function and higher isometric abductor muscle force

Aims

This study aimed to use intraoperative free electromyography to examine how the placement of a retractor at different positions along the anterior acetabular wall may affect the femoral nerve during total hip arthroplasty (THA) when undertaken using the direct anterior approach (THA-DAA).

Aims

Optimal exposure through the direct anterior approach (DAA) for total hip arthroplasty (THA) conducted on a regular operating theatre table is achieved with a standardized capsular releasing sequence in which the anterior capsule can be preserved or resected. We hypothesized that clinical outcomes and implant positioning would not be different in case a capsular sparing (CS) technique would be compared to capsular resection (CR).

Aims

The gluteus minimus (GMin) and gluteus medius (GMed) have unique structural and functional segments that may be affected to varying degrees, by end-stage osteoarthritis (OA) and normal ageing. We used data from patients with end-stage OA and matched healthy controls to 1) quantify the atrophy of the GMin and GMed in the two groups and 2) describe the distinct patterns of the fatty infiltration in the different segments of the GMin and GMed in the two groups.

Aims

Uncemented metal acetabular components show good osseointegration, but material stiffness causes stress shielding and retroacetabular bone loss. Cemented monoblock polyethylene components load more physiologically; however, the cement bone interface can suffer fibrous encapsulation and loosening. It was hypothesized that an uncemented titanium-sintered monoblock polyethylene component may offer the optimum combination of osseointegration and anatomical loading.

Aims

Complex total hip arthroplasty (THA) with subtrochanteric shortening osteotomy is necessary in conditions other than developmental dysplasia of the hip (DDH) and septic arthritis sequelae with significant proximal femur migration. Our aim was to evaluate the hip centre restoration with THAs in these hips.

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This study aimed to explore whether intraoperative nerve monitoring can identify risk factors and reduce the incidence of nerve injury in patients with high-riding developmental dysplasia.

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Patients may present with concurrent symptomatic osteoarthritis (OA) of the hip and degenerative disorders of the lumbar spine, with surgical treatment being indicated for both. Whether arthroplasty of the hip or spinal surgery should be performed first remains uncertain.

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The aim of this study was to determine the stability of a new short femoral stem compared with a conventional femoral stem in patients undergoing cementless total hip arthroplasty (THA), in a prospective randomized controlled trial using radiostereometric analysis (RSA).

Aims

The aim of this study was to compare early functional and health related quality of life outcomes (HRQoL) in patients who have undergone total hip arthroplasty (THA) using a bone conserving short stem femoral component and those in whom a conventional length uncemented component was used. Outcome was assessed using a validated performance based outcome instrument as well as patient reported outcome measures (PROMs).

Aims

In order to prevent dislocation of the hip after total hip arthroplasty (THA), patients have to adhere to precautions in the early post-operative period. The hypothesis of this study was that a protocol with minimal precautions after primary THA using the posterolateral approach would not increase the short-term (less than three months) risk of dislocation.

Hip and groin injuries are common in athletes who take part in high level sports. Adductor muscle tendon injuries represent a small but important number of these injuries. Avulsion of the tendons attached to the symphysis pubis has previously been described: these can be managed both operatively and non-operatively. We describe an uncommon variant of this injury, namely complete avulsion of the adductor sleeve complex: this includes adductor longus, pectineus and rectus abdominis. We go on to describe a surgical technique which promotes a full return to the pre-injury level of sporting activity.

Over a period of ten years, 15 high-level athletes with an MRI-confirmed acute adductor complex avulsion injury (six to 34 days old) underwent surgical repair. The operative procedure consisted of anatomical re-attachment of the avulsed tissues in each case and mesh reinforcement of the posterior inguinal wall in seven patients. All underwent a standardised rehabilitation programme, which was then individualised to be sport-specific.

One patient developed a superficial wound infection, which was successfully treated with antibiotics. Of the 15 patients, four complained of transient local numbness which resolved in all cases. All patients (including seven elite athletes) returned to their previous level of participation in sport.

Cite this article: Bone Joint J 2015;97-B:1488–92.

We have investigated whether control of balance is improved during stance and gait and sit-to-stand tasks after unilateral total hip replacement undertaken for osteoarthritis of the hip.

We examined 25 patients with a mean age of 67 years (sd 6.2) before and at four and 12 months after surgery and compared the findings with those of 50 healthy age-matched control subjects. For all tasks, balance was quantified using angular measurements of movement of the trunk.

Before surgery, control of balance during gait and sit-to-stand tasks was abnormal in patients with severe osteoarthritis of the hip, while balance during stance was similar to that of the healthy control group. After total hip replacement, there was a progressive improvement at four and 12 months for most gait and sit-to-stand tasks and in the time needed to complete them. By 12 months, the values approached those of the control group. However, trunk pitch (forwards-backwards) and roll (side-to-side) velocities were less stable (greater than the control) when walking over barriers as was roll for the sit-to-stand task, indicative of a residual deficit of balance.

Our data suggest that patients with symptomatic osteoarthritis of the hip have marked deficits of balance in gait tasks, which may explain the increased risk of falling which has been reported in some epidemiological studies. However, total hip replacement may help these patients to regain almost normal control of balance for some gait tasks, as we found in this study. Despite the improvement in most components of balance, however, the deficit in the control of trunk velocity during gait suggests that a cautious follow-up is required after total hip replacement regarding the risk of a fall, especially in the elderly.

We compared the dynamic instability of 25 dysplastic hips in 25 patients using triaxial accelerometry before and one year after periacetabular osteotomy. We also evaluated the hips clinically using the Harris hip score and assessed acetabular orientation by radiography before surgery and after one year. The mean overall magnitude of acceleration was significantly reduced from 2.30 m/s² (sd 0.57) before operation to 1.55 m/s² (sd 0.31) afterwards. The mean Harris hip score improved from 78.08 (47 to 96) to 95.36 points (88 to 100). The radiographic parameters all showed significant improvements.

This study suggests that periacetabular osteotomy provides pain relief, improves acetabular cover and reduces the dynamic instability in patients with dysplastic hips.

We reviewed 111 hemispherical Duraloc series-500 acetabular components with a minimum follow-up of 12 years. The mean clinical and radiological follow-up was 13.4 years (12 to 15). A Profile hydroxyapatite-coated anatomical femoral component was used in each case. Six patients had a late dislocation, for whom the polyethylene liner was exchanged. Each acetabular component was well fixed and all femoral components showed signs of bone ingrowth. The mean rate of femoral head penetration was 0.10 mm/year (0.021 to 0.481). The probability of not developing femoral cortical hypertrophy and proximal osteopenia by 12 years was 80.2% (95% confidence interval, 72.7 to 87.6) and 77.5% (95% confidence interval, 69.7 to 85.2), respectively. Despite these good clinical results, further follow-up is needed to determine whether these prostheses will loosen with time.