The aim of this study was to investigate the incidence of dysplasia in the ‘normal’ contralateral hip in patients with unilateral developmental dislocation of the hip (DDH) and to evaluate the long-term prognosis of such hips. A total of 48 patients (40 girls and eight boys) were treated for late-detected unilateral DDH between 1958 and 1962. After preliminary skin traction, closed reduction was achieved at a mean age of 17.8 months (4 to 65) in all except one patient who needed open reduction. In 25 patients early derotation femoral osteotomy of the contralateral hip had been undertaken within three years of reduction, and later surgery in ten patients. Radiographs taken during childhood and adulthood were reviewed. The mean age of the patients was 50.9 years (43 to 55) at the time of the latest radiological review. In all, eight patients (17%) developed dysplasia of the contralateral hip, defined as a centre-edge (CE) angle < 20° during childhood or at skeletal maturity. Six of these patients underwent surgery to improve cover of the femoral head; the dysplasia improved in two after varus femoral osteotomy and in two after an acetabular shelf operation. During long-term follow-up the dysplasia deteriorated to subluxation in two patients (CE angles 4° and 5°, respectively) who both developed osteoarthritis (OA), and one of these underwent total hip replacement at the age of 49 years. In conclusion, the long-term prognosis for the contralateral hip was relatively good, as OA occurred in only two hips (4%) at a mean follow-up of 50 years. Regular review of the ‘normal’ side is indicated, and corrective surgery should be undertaken in those who develop subluxation. Cite this article: Bone Joint J 2014; 96-B:1161–6

We reviewed, at an average age of 46 years, a series of 61 patients treated for unilateral slipped upper femoral epiphysis. At maturity there had been slipping of the contralateral hip in 11 patients (18%) and another 14 (23%) had originally had evidence of bilateral slipping when the primary radiographs were reviewed. In only two of these 25 patients (8%) was the slipping of the contralateral hip symptomatic. The incidence of early osteoarthritis of the contralateral hip was 7 of 36 with no slip, 5 of 16 with an untreated slip and 1 of 9 with a slip pinned in situ. If all 61 contralateral hips had been prophylactically pinned at the primary admission, 36 of the operations (59%) would have been unnecessary. We recommend that prophylactic pinning of the contralateral hip should not be standard, but that lateral radiography by the Billing technique be repeated every third to fourth month until closure of the growth plate begins. Hips in which a slip occurs should be pinned in situ

In the majority of patients with slipped upper femoral epiphysis only one hip is involved at primary diagnosis. However, the contralateral hip often becomes involved over time. There are no reliable factors predicting a contralateral slip. Whether or not the contralateral hip should undergo prophylactic fixation is a matter of controversy. We present a number of essential points that have to be considered both when choosing to fix the contralateral hip prophylactically as well as when refraining from surgery and instead following the patients with repeat radiographs

Aims

The purpose of this study was to examine whether leg-length discrepancy (LLD) following unilateral total hip arthroplasty (THA) affects the incidence of contralateral head collapse and subsequent THA in patients with bilateral osteonecrosis, and to determine factors associated with subsequent collapse.

Aims. This study aimed to compare mortality in trochanteric AO/OTA A1 and A2 fractures treated with an intramedullary nail (IMN) or sliding hip screw (SHS). The primary endpoint was 30-day mortality, with secondary endpoints at 0 to 1, 2 to 7, 8 to 30, 90, and 365 days. Methods. We analyzed data from 26,393 patients with trochanteric AO/OTA A1 and A2 fractures treated with IMNs (n = 9,095) or SHSs (n = 17,298) in the Norwegian Hip Fracture Register (January 2008 to December 2020). Exclusions were made for patients aged < 60 years, pathological fractures, pre-2008 operations, contralateral hip fractures, fractures other than trochanteric A1/A2, and treatments other than IMNs or SHSs. Kaplan-Meier and Cox regression analyses adjusted for type of fracture, age, sex, cognitive impairment, American Society of Anesthesiologists (ASA) grade, and time period were conducted, along with calculations for number needed to harm (NNH). Results. In unadjusted analyses, there was no significant difference between IMN and SHS patient survival at 30 days (91.8% vs 91.1%; p = 0.083) or 90 days (85.4% vs 84.5%; p = 0.065), but higher one-year survival for IMNs (74.5% vs 73.3%; p = 0.031) compared with SHSs. After adjustments, no significant difference in 30-day mortality was found (hazard rate ratio (HRR) 0.94 (95% confidence interval (CI) 0.86 to 1.02(; p = 0.146). IMNs exhibited higher mortality at 0 to 1 days (HRR 1.63 (95% CI 1.13 to 2.34); p = 0.009) compared with SHSs, with a NNH of 556, but lower mortality at 8 to 30 days (HRR 0.89 (95% CI 0.80 to 1.00); p = 0.043). No differences were observed in mortality at 2 to 7 days (HRR 0.94 (95% CI 0.79 to 1.11); p = 0.434), 90 days (HRR 0.95 (95% CI 0.89 to 1.02); p = 0.177), or 365 days (HRR 0.97 (95% CI 0.92 to 1.02); p = 0.192). Conclusion. This study found no difference in 30-day mortality between IMNs and SHSs. However, IMNs were associated with a higher mortality at 0 to 1 days and a marginally lower mortality at 8 to 30 days compared with SHSs. The observed differences in mortality were small and should probably not guide choice of treatment. Cite this article: Bone Joint J 2024;106-B(6):603–612

Aims. The aims of this study were to evaluate the abductor function in moderate and severe slipped capital femoral epiphysis (SCFE), comparing the results of a corrective osteotomy at the base of the femoral neck and osteoplasty with 1) in situ epiphysiodesis for mild SCFE, 2) contralateral unaffected hips, and 3) hips from healthy individuals. Patients and Methods. A total of 24 patients (mean age 14.9 years (. sd. 1.6); 17 male and seven female patients) with moderate or severe SCFE (28 hips) underwent base of neck osteotomy and osteoplasty between 2012 and 2015. In situ epiphysiodesis was performed in seven contralateral hips with mild slip. A control cohort was composed of 15 healthy individuals (mean age 16.5 years (. sd. 2.5); six male and nine female patients). The abductor function was assessed using isokinetic dynamometry and range of abduction, with a minimum one-year follow-up. Results. We found no differences in mean peak abductor torque between the hips that underwent osteotomy and those that received in situ epiphysiodesis (p = 0.63), but the torque was inferior in comparison with contralateral hips without a slip (p < 0.01) and hips from control individuals (p < 0.001). The abduction strength was positively correlated with the range of hip abduction (R = 0.36; p < 0.001). Conclusion. Although the abductor strength was not restored to normal levels, moderate and severe SCFE treated with osteotomy at the base of the femoral neck and osteoplasty showed abductor function similar to in situ epiphysiodesis in hips with less severe displacement. Cite this article: Bone Joint J 2018;100-B:1524–32

Controversy remains whether the contralateral hip should be fixed in patients presenting with unilateral slipped capital femoral epiphysis (SCFE). This retrospective study compares the outcomes and cost of those patients who had prophylactic fixation with those who did not. Between January 2000 and December 2010 a total of 50 patients underwent unilateral fixation and 36 had prophylactic fixation of the contralateral hip. There were 54 males and 32 females with a mean age of 12.3 years (9 to 16). The rate of a subsequent slip without prophylactic fixation was 46%. The risk of complications was greater, the generic health measures (Short Form-12 physical (p < 0.001) and mental (p = 0.004) summary scores) were worse. Radiographic cam lesions in patients presenting with unilateral SCFE were only seen in patients who did not have prophylactic fixation. Furthermore, prophylactic fixation of the contralateral hip was found to be a cost-effective procedure, with a cost per quality adjusted life year gained of £1431 at the time of last follow-up. . Prophylactic fixation of the contralateral hip is a cost-effective operation that limits the morbidity from the complications of a further slip, and the diminished functional outcome associated with unilateral fixation. . Cite this article: Bone Joint J 2015;97-B:1428–34

Aims. Spinopelvic mobility plays an important role in functional acetabular component position following total hip arthroplasty (THA). The primary aim of this study was to determine if spinopelvic hypermobility persists or resolves following THA. Our second aim was to identify patient demographic or radiological factors associated with hypermobility and resolution of hypermobility after THA. Methods. This study investigated patients with preoperative posterior hypermobility, defined as a change in sacral slope (SS) from standing to sitting (ΔSS. stand-sit. ) ≥ 30°. Radiological spinopelvic parameters, including SS, pelvic incidence (PI), lumbar lordosis (LL), PI-LL mismatch, anterior pelvic plane tilt (APPt), and spinopelvic tilt (SPT), were measured on preoperative imaging, and at six weeks and a minimum of one year postoperatively. The severity of bilateral hip osteoarthritis (OA) was graded using Kellgren-Lawrence criteria. Results. A total of 136 patients were identified as having preoperative spinopelvic hypermobility. At one year after THA, 95% (129/136) of patients were no longer categorized as hypermobile on standing and sitting radiographs (ΔSS. stand-sit. < 30°). Mean ΔSS. stand-sit. decreased from 36.4° (SD 5.1°) at baseline to 21.4° (SD 6.6°) at one year (p < 0.001). Mean SS. seated. increased from baseline (11.4° (SD 8.8°)) to one year after THA by 11.5° (SD 7.4°) (p < 0.001), which correlates to an 8.5° (SD 5.5°) mean decrease in seated functional cup anteversion. Contralateral hip OA was the only radiological predictor of hypermobility persisting at one year after surgery. The overall reoperation rate was 1.5%. Conclusion. Spinopelvic hypermobility was found to resolve in the majority (95%) of patients one year after THA. The increase in SS. seated. was clinically significant, suggesting that current target recommendations for the hypermobile patient (decreased anteversion and inclination) should be revisited. Cite this article: Bone Joint J 2021;103-B(12):1766–1773

Aims. Cross-table lateral (CTL) radiographs are commonly used to measure acetabular component anteversion after total hip arthroplasty (THA). The CTL measurements may differ by > 10° from CT scan measurements but the reasons for this discrepancy are poorly understood. Anteversion measurements from CTL radiographs and CT scans are compared to identify spinopelvic parameters predictive of inaccuracy. Methods. THA patients (n = 47; 27 males, 20 females; mean age 62.9 years (SD 6.95)) with preoperative spinopelvic mobility, radiological analysis, and postoperative CT scans were retrospectively reviewed. Acetabular component anteversion was measured on postoperative CTL radiographs and CT scans using 3D reconstructions of the pelvis. Two cohorts were identified based on a CTL-CT error of ≥ 10° (n = 11) or < 10° (n = 36). Spinopelvic mobility parameters were compared using independent-samples t-tests. Correlation between error and mobility parameters were assessed with Pearson’s coefficient. Results. Patients with CTL error > 10° (10° to 14°) had stiffer lumbar spines with less mean lumbar flexion (38.9°(SD 11.6°) vs 47.4° (SD 13.1°); p = 0.030), different sagittal balance measured by pelvic incidence-lumbar lordosis mismatch (5.9° (SD 18.8°) vs -1.7° (SD 9.8°); p = 0.042), more pelvic extension when seated (pelvic tilt -9.7° (SD 14.1°) vs -2.2° (SD 13.2°); p = 0.050), and greater change in pelvic tilt between supine and seated positions (12.6° (SD 12.1°) vs 4.7° (SD 12.5°); p = 0.036). The CTL measurement error showed a positive correlation with increased CTL anteversion (r = 0.5; p = 0.001), standing lordosis (r = 0.23; p = 0.050), seated lordosis (r = 0.4; p = 0.009), and pelvic tilt change between supine and step-up positions (r = 0.34; p = 0.010). Conclusion. Differences in spinopelvic mobility may explain the variability of acetabular anteversion measurements made on CTL radiographs. Patients with stiff spines and increased compensatory pelvic movement have less accurate measurements on CTL radiographs. Flexion of the contralateral hip is required to obtain clear CTL radiographs. In patients with lumbar stiffness, this movement may extend the pelvis and increase anteversion of the acetabulum on CTL views. Reliable analysis of acetabular component anteversion in this patient population may require advanced imaging with a CT scan. Cite this article: Bone Joint J 2021;103-B(7 Supple B):59–65

Aims. The aims of this study were to describe the course of non-operatively managed, bilateral Perthes’ disease, and to determine specific prognostic factors for the radiographic and clinical outcome. . Patients and Methods. We identified 40 children with a mean age of 5.9 years (1.8 to 13.5), who were managed non-operatively for bilateral Perthes’ disease from our prospective, multicentre study of this condition, which included all children in Norway who were diagnosed with Perthes’ disease in the five-year period between 1996 and 2000. All children were followed up for five years. . The hips were classified according to the Catterall classification. A modified three-group Stulberg classification was used as an outcome measure, with a spherical femoral head being defined as a good outcome, an oval head as fair, and a flat femoral head as a poor outcome. . Results. Concurrent, simultaneous bilateral Perthes’ disease was seen in 23 children and 17 had the sequential onset of bilateral disease. The mean delay in onset for the second hip in the latter group was 1.9 years (0.3 to 5.5). . The five-year radiographic outcome was good in 30 (39%), fair in 25 (33%) and poor in 21 (28%) of the hips. The strongest predictors of poor outcome were > 50% necrosis of the femoral head, with odds ratio (OR) 19.6, and age at diagnosis > 6 years (OR 3.3). Other risk factors for poor outcome were the timing of the onset of disease, where children with the sequential onset of bilateral disease had a higher risk than those with the concurrent onset of bilateral disease (p = 0.021, chi-squared test). . Following a diagnosis of Perthes’ disease in one hip, there was a 5% chance of developing it in the contralateral hip. . Conclusion. These results imply that we need to distinguish between children with concurrent onset and those with sequential onset of bilateral Perthes’ disease, as the outcomes may be different. This has not been previously described. Children with concurrent onset of bilateral disease had a similar outcome to our previous series of those with unilateral disease, whereas children with sequential onset of bilateral disease had a worse prognosis. The increased risk of developing Perthes’ disease in the contralateral hip in those with unilateral disease is important information for the child and parents. . Cite this article: Bone Joint J 2016;98-B:569–75

Aims. Increasingly, patients with bilateral hip arthritis wish to undergo staged total hip arthroplasty (THA). With the rise in demand for arthroplasty, perioperative risk assessment and counselling is crucial for shared decision making. However, it is unknown if complications that occur after a unilateral hip arthroplasty predict complications following surgery of the contralateral hip. Patients and Methods. We used nationwide linked discharge data from the Healthcare Cost and Utilization Project between 2005 and 2014 to analyze the incidence and recurrence of complications following the first- and second-stage operations in staged bilateral total hip arthroplasty (BTHAs). Complications included perioperative medical adverse events within 30 to 60 days, and infection and mechanical complications within one year. Conditional probabilities and odds ratios (ORs) were calculated to determine whether experiencing a complication after the first stage of surgery increased the risk of developing the same complication after the second stage. Results. A total of 13 829 patients (5790 men and 8039 women) who underwent staged BTHAs were analyzed. The mean age at first operation was 62.9 years (14 to 95). For eight of the 12 outcomes evaluated, patients who experienced the outcome following the first arthroplasty had a significantly increased probability and odds of developing that same complication following the second arthroplasty, compared with those who did not experience the complication after the first surgery. This was true for digestive complications (OR 25.67, 95% confidence interval (CI) 13.86 to 46.08; p < 0.001), urinary complications (OR 6.48, 95% CI 1.7 to 20.73; p = 0.01), haematoma (OR 12.17, 95% CI 4.55 to 31.14; p < 0.001), deep vein thrombosis (OR 4.82, 95% CI 2.34 to 9.65; p < 0.001), pulmonary embolism (OR 12.03, 95% CI 2.02 to 46.77; p = 0.01), deep hip infection (OR 534.21, 95% CI 314.96 to 909.25; p < 0.001), superficial hip infection (OR 1574.99, 95% CI 269.83 to 9291.81; p < 0.001), and mechanical malfunction (OR 117.49, 95% CI 91.55 to 150.34; p < 0.001). Conclusion. The occurrence of certain complications after unilateral THA is associated with an increased risk of the same complication occurring after staged arthroplasty of the contralateral hip. Patients who experience these complications after unilateral hip arthroplasty should be appropriately counselled regarding their risk profile prior to undergoing staged contralateral hip arthroplasty. Cite this article: Bone Joint J 2019;101-B(6 Supple B):77–83

Between July 1994 and June 2004, 60 patients with 76 slipped upper femoral epiphyses were managed within the adult trauma service of three hospitals. Treatment was by a single cannulated screw. Of these cases, 53 were unilateral, in 17 of which uncomplicated prophylactic fixation of the contralateral hip was performed. Of the other 36 cases, nine presented with a subsequent slip despite ongoing out-patient care. The subsequent slip was unpredictable in timing and unrelated to the age at the initial slip. It was more often unstable and in one case avascular necrosis developed. The overall rate of avascular necrosis, although in accordance with the literature, was 60% in acute unstable slips with a slip angle greater than 40°. In our experience, prophylactic fixation was safer than continued observation of the contralateral hip

Salter innominate osteotomy is an effective reconstructive procedure for the treatment of developmental dysplasia of the hip (DDH), but some children have a poor outcome at skeletal maturity. In order to investigate factors associated with an unfavourable outcome, we assessed the development of the contralateral hip. We retrospectively reviewed 46 patients who underwent a unilateral Salter osteotomy at between five and seven years of age, with a mean follow-up of 10.3 years (7 to 20). The patients were divided into three groups according to the centre–edge angle (CEA) of the contralateral hip at skeletal maturity: normal (> 25°, 22 patients), borderline (20° to 25°, 17 patients) and dysplastic (<  20°, 7 patients). The CEA of the affected hip was measured pre-operatively, at eight to nine years of age, at 11 to 12 years of age and at skeletal maturity. The CEA of the affected hip was significantly smaller in the borderline and dysplastic groups at 11 and 12 years of age (p = 0.012) and at skeletal maturity (p = 0.017) than in the normal group. Severin group III was seen in two (11.8%) and four hips (57.1%) of the borderline and dysplastic groups, respectively (p < 0.001). . Limited individual development of the acetabulum was associated with an unfavourable outcome following Salter osteotomy. Cite this article: Bone Joint J 2014;96-B:1419–23

There have been several studies examining the association between the morphological characteristics seen in acetabular dysplasia and the incidence of the osteoarthritis (OA). However, most studies focus mainly on acetabular morphological analysis, and few studies have scrutinised the effect of femoral morphology. In this study we enrolled 36 patients with bilateral acetabular dysplasia and early or mid-stage OA in one hip and no OA in the contralateral hip. CT scans were performed from the iliac crest to 2 cm inferior to the tibial tuberosity, and the morphological characteristics of both acetabulum and femur were studied. . In addition, 200 hips in 100 healthy volunteer Chinese adults formed a control group. The results showed that the dysplastic group with OA had a significantly larger femoral neck anteversion and a significantly shorter abductor lever arm than both the dysplastic group without OA and the controls. Femoral neck anteversion had a significant negative correlation with the length of the abductor lever arm and we conclude that it may contribute to the development of OA in dysplastic hips. Cite this article: Bone Joint J 2014; 96-B:1586–93

We investigated the effect of calcitonin in the prevention of acute bone loss after a pertrochanteric fracture and its ability to reduce the incidence of further fractures in the same patient. Fifty women aged between 70 and 80 years who had a pertrochanteric fracture of the hip were randomly allocated to group A (200 IU of nasal salmon calcitonin daily for three months) or group B (placebo). Patients in group A showed a significantly higher level of total alkaline phosphatase and osteocalcin on the 15th day after injury and a significantly higher level of bone alkaline phosphatase on the 90th day after surgery. These patients also had significantly lower levels of urinary C-telopeptide (CrossLaps) on the 15th, 45th and 90th days after injury and lower levels of urinary hydroxyproline on the 15th and 45th days after injury. Patients in group A had significantly higher bone mineral density at all recorded sites except the greater trochanter at three months and one year after operation. After a four-year period of clinical observation, five patients (24%) in group B sustained a new fracture, in four of whom (20%) it was of the contralateral hip. Our findings show that calcitonin reduces acute bone loss in patients with pertrochanteric fractures and may prevent the occurrence of new fractures of the contralateral hip in the elderly

The aim of this study was to examine the loading of the other joints of the lower limb in patients with unilateral osteoarthritis (OA) of the knee. We recruited 20 patients with no other symptoms or deformity in the lower limbs from a consecutive cohort of patients awaiting knee replacement. Gait analysis and electromyographic recordings were performed to determine moments at both knees and hips, and contraction patterns in the medial and lateral quadriceps and hamstrings bilaterally. The speed of gait was reduced in the group with OA compared with the controls, but there were only minor differences in stance times between the limbs. Patients with OA of the knee had significant increases in adduction moment impulse at both knees and the contralateral hip (adjusted p-values: affected knee: p < 0.01, unaffected knee p = 0.048, contralateral hip p = 0.03), and significantly increased muscular co-contraction bilaterally compared with controls (all comparisons for co-contraction, p < 0.01). The other major weight-bearing joints are at risk from abnormal biomechanics in patients with unilateral OA of the knee. Cite this article: Bone Joint J 2013;95-B:348–53

Aims

The aim of this study was to compare the biomechanical models of two frequently used techniques for reconstructing severe acetabular defects with pelvic discontinuity in revision total hip arthroplasty (THA) – the Trabecular Metal Acetabular Revision System (TMARS) and custom triflange acetabular components (CTACs) – using virtual modelling.

Aims. The aim of this study was to assess the functional gain achieved following hip resurfacing arthroplasty (HRA). Patients and Methods. A total of 28 patients (23 male, five female; mean age, 56 years (25 to 73)) awaiting Birmingham HRA volunteered for this prospective gait study, with an age-matched control group of 26 healthy adults (16 male, ten female; mean age, 56 years (33 to 84)). The Oxford Hip Score (OHS) and gait analysis using an instrumented treadmill were used preoperatively and more than two years postoperatively to measure the functional change attributable to the intervention. Results. The mean OHS improved significantly from 27 to 46 points (p < 0.001) at a mean of 29 months (12 to 60) after HRA. The mean metal ion levels at a mean 32 months (13 to 60) postoperatively were 1.71 (0.77 to 4.83) µg/l (ppb) and 1.77 (0.68 to 4.16) µg/l (ppb) for cobalt and chromium, respectively. When compared with healthy controls, preoperative patients overloaded the contralateral good hip, limping significantly. After HRA, patients walked at high speeds, with symmetrical gait, statistically indistinguishable from healthy controls over almost all characteristics. The control group could only be distinguished by an increased push-off force at higher speeds, which may reflect the operative approach. Conclusion. Patients undergoing HRA improved their preoperative gait pattern of a significant limp to a symmetrical gait at high speeds and on inclines, almost indistinguishable from normal controls. HRA with an approved device offers substantial functional gains, almost indistinguishable from healthy controls. Cite this article: Bone Joint J 2019;101-B:1423–1430

We have compared the biomechanical nature of the reconstruction of the hip in conventional total hip arthroplasty (THA) and surface replacement arthroplasty (SRA) in a randomised study involving 120 patients undergoing unilateral primary hip replacement. The contralateral hip was used as a control. Post-operatively, the femoral offset was significantly increased with THA (mean 5.1 mm; −2.8 to 11.6) and decreased with SRA (mean −3.3 mm; −8.9 to 8.2). Femoral offset was restored within . sd. 4 mm in 14 (25%) of those with THA and in 28 (57%) of the patients receiving SRA (p < 0.001). In the THA group, the leg was lengthened by a mean of 2.6 mm (−6.04 to +12.9), whereas it was shortened by a mean of 1.9 mm (−7.1 to +2.05) in the SRA group, compared with the contralateral side. Leg-length inequality was restored within . sd. 4 mm in 42 (86%) of the SRA and 33 (60%) of the THA patients. The radiological parameters of acetabular reconstruction were similar in both groups. Restoration of the normal proximal femoral anatomy was more precise with SRA. The enhanced stability afforded by the use of a large-diameter femoral head avoided over-lengthening of the limb or increased offset to improve soft-tissue tension as occurs sometimes in THA. In a subgroup of patients with significant pre-operative deformity, restoration of the normal hip anatomy with lower pre-operative femoral offset or significant shortening of the leg was still possible with SRA

Aims

To investigate the extent of bone development around the scaffold of custom triflange acetabular components (CTACs) over time.