Between 2003 and 2007, 99 knees in 77 patients underwent opening wedge high tibial osteotomy. We evaluated the effect of initial stable fixation combined with an artificial bone substitute on the mid- to long-term outcome after medial opening-wedge high tibial osteotomy (HTO) for medial compartmental osteoarthritis or spontaneous osteonecrosis of the knee in 78 knees in 64 patients available for review at a minimum of five years (mean age 68 years; 49 to 82). The mean follow-up was 6.5 years (5 to 10). The mean Knee Society knee score and function score improved from 49.6 (. sd. 11.4, 26 to 72) and 56.6 (. sd. 15.6, 5 to 100) before surgery to 88.1 (. sd. 12.5, 14 to 100) and 89.4 (. sd. 15.6, 5 to 100) at final follow-up (p <  0.001) respectively. There were no significant differences between patients aged ≥ 70 and < 70 years. The mean standing femorotibial angle was corrected significantly from 181.7° (. sd.  2.7°, 175° to 185°) pre-operatively to 169.7° (. sd. 2.4°, 164° to 175°) at one year’s follow-up (p < 0.001) and 169.6° (. sd. 3.0°, 157° to 179°) at the final follow-up (p = 0.69 vs one year). . Opening-wedge HTO using a stable plate fixation system combined with a bone substitute is a reliable procedure that provides excellent results. Although this treatment might seem challenging for older patients, our results strongly suggest that the results are equally good. Cite this article: Bone Joint J 2014;96-B:339–44

Aims

To identify a suite of the key physical, emotional, and social outcomes to be employed in clinical practice and research concerning Perthes' disease in children.

We hypothesised that a large acromial cover with an upwardly tilted glenoid fossa would be associated with degenerative rotator cuff tears (RCTs), and conversely, that a short acromion with an inferiorly inclined glenoid would be associated with glenohumeral osteoarthritis (OA). This hypothesis was tested using a new radiological parameter, the critical shoulder angle (CSA), which combines the measurements of inclination of the glenoid and the lateral extension of the acromion (the acromion index). The CSA was measured on standardised radiographs of three groups: 1) a control group of 94 asymptomatic shoulders with normal rotator cuffs and no OA; 2) a group of 102 shoulders with MRI-documented full-thickness RCTs without OA; and 3) a group of 102 shoulders with primary OA and no RCTs noted during total shoulder replacement. The mean CSA was 33.1° (26.8° to 38.6°) in the control group, 38.0° (29.5° to 43.5°) in the RCT group and 28.1° (18.6° to 35.8°) in the OA group. Of patients with a CSA > 35°, 84% were in the RCT group and of those with a CSA < 30°, 93% were in the OA group. We therefore concluded that primary glenohumeral OA is associated with significantly smaller degenerative RCTs with significantly larger CSAs than asymptomatic shoulders without these pathologies. These findings suggest that individual quantitative anatomy may imply biomechanics that are likely to induce specific types of degenerative joint disorders. Cite this article: Bone Joint J 2013;95-B:935–41

We investigated the spinopelvic morphology and global sagittal balance of patients with a degenerative retrolisthesis or anterolisthesis. A total of 269 consecutive patients with a degenerative spondylolisthesis were included in this study. There were 95 men and 174 women with a mean age of 64.3 years (. sd. 10.5; 40 to 88). A total of 106 patients had a pure retrolisthesis (R group), 130 had a pure anterolisthesis (A group), and 33 had both (R+A group). A backward slip was found in the upper lumbar levels (mostly L2 or L3) with an almost equal gender distribution in both the R and R+A groups. The pelvic incidence and sacral slope of the R group were significantly lower than those of the A (both p < 0.001) and R+A groups (both p < 0.001). The lumbar lordosis of the R+A group was significantly greater than that of the R (p = 0.025) and A groups (p = 0.014). The C7 plumb line of the R group was located more posteriorly than that of the A group (p = 0.023), but was no different from than that of the R+A group (p = 0.422). The location of C7 plumb line did not differ between the three groups (p = 0.068). The spinosacral angle of the R group was significantly smaller than that of the A group (p < 0.001) and R+A group (p < 0.001). Our findings imply that there are two types of degenerative retrolisthesis: one occurs primarily as a result of degeneration in patients with low pelvic incidence, and the other occurs secondarily as a compensatory mechanism in patients with an anterolisthesis and high pelvic incidence. Cite this article: Bone Joint J 2013;95-B:1244–9

We compared lower limb coronal alignment measurements obtained pre- and post-operatively with long-leg radiographs and computer navigation in patients undergoing primary total knee replacement (TKR). A series of 185 patients had their pre- and post-implant radiological and computer-navigation system measurements of coronal alignment compared using the Bland-Altman method. The study included 81 men and 104 women with a mean age of 68.5 years (32 to 87) and a mean body mass index of 31.7 kg/m. 2. (19 to 49). Pre-implant Bland–Altman limits of agreement were -9.4° to 8.6° with a repeatability coefficient of 9.0°. The Bland–Altman plot showed a tendency for the radiological measurement to indicate a higher level of pre-operative deformity than the corresponding navigation measurement. Post-implant limits of agreement were -5.0° to 5.4° with a repeatability coefficient of 5.2°. The tendency for valgus knees to have greater deformity on the radiograph was still seen, but was weaker for varus knees. . The alignment seen or measured intra-operatively during TKR is not necessarily the same as the deformity seen on a standing long-leg radiograph either pre- or post-operatively. Further investigation into the effect of weight-bearing and surgical exposure of the joint on the mechanical femorotibial angle is required to enable the most appropriate intra-operative alignment to be selected

Patient-specific cutting guides (PSCGs) are designed to improve the accuracy of alignment of total knee replacement (TKR). We compared the accuracy of limb alignment and component positioning after TKR performed using PSCGs or conventional instrumentation. A total of 80 patients were randomised to undergo TKR with either of the different forms of instrumentation, and radiological outcomes and peri-operative factors such as operating time were assessed. No significant difference was observed between the groups in terms of tibiofemoral angle or femoral component alignment. Although the tibial component in the PSCGs group was measurably closer to neutral alignment than in the conventional group, the size of the difference was very small (89.8° (. sd. 1.2) vs 90.5° (. sd. 1.6); p = 0.030). This new technology slightly shortened the bone-cutting time by a mean of 3.6 minutes (p < 0.001) and the operating time by a mean 5.1 minutes (p = 0.019), without tangible differences in post-operative blood loss (p = 0.528) or need for blood transfusion (p = 0.789). This study demonstrated that both PSCGs and conventional instrumentation restore limb alignment and place the components with the similar accuracy. The minimal advantages of PSCGs in terms of consistency of alignment or operative time are unlikely to be clinically relevant. Cite this article: Bone Joint J 2013;95-B:354–9

Version of the femoral stem is an important factor influencing the risk of dislocation after total hip replacement (THR) as well as the position of the acetabular component. However, there is no radiological method of measuring stem anteversion described in the literature. We propose a radiological method to measure stem version and have assessed its reliability and validity. In 36 patients who underwent THR, a hip radiograph and CT scan were taken to measure stem anteversion. The radiograph was a modified Budin view. This is taken as a posteroanterior radiograph in the sitting position with 90° hip flexion and 90° knee flexion and 30° hip abduction. The angle between the stem-neck axis and the posterior intercondylar line was measured by three independent examiners. The intra- and interobserver reliabilities of each measurement were examined. The radiological measurements were compared with the CT measurements to evaluate their validity. The mean radiological measurement was 13.36° (. sd. 6.46) and the mean CT measurement was 12.35° (. sd. 6.39) (p = 0.096). The intra- and interobserver reliabilities were excellent for both measurements. The radiological measurements correlated well with the CT measurements (p = 0.001, r = 0.877). The modified Budin method appears reliable and valid for the measurement of femoral stem anteversion. Cite this article: Bone Joint J 2013;95-B:877–80

This study provides recommendations on the position of the implant in reverse shoulder replacement in order to minimise scapular notching and osteophyte formation. Radiographs from 151 patients who underwent primary reverse shoulder replacement with a single prosthesis were analysed at a mean follow-up of 28.3 months (24 to 44) for notching, osteophytes, the position of the glenoid baseplate, the overhang of the glenosphere, and the prosthesis scapular neck angle (PSNA). A total of 20 patients (13.2%) had a notch (16 Grade 1 and four Grade 2) and 47 (31.1%) had an osteophyte. In patients without either notching or an osteophyte the baseplate was found to be positioned lower on the glenoid, with greater overhang of the glenosphere and a lower PSNA than those with notching and an osteophyte. Female patients had a higher rate of notching than males (13.3% vs 13.0%) but a lower rate of osteophyte formation (22.9% vs 50.0%), even though the baseplate was positioned significantly lower on the glenoid in females (p = 0.009) and each had a similar mean overhang of the glenosphere. Based on these findings we make recommendations on the placement of the implant in both male and female patients to avoid notching and osteophyte formation. Cite this article: Bone Joint J 2013;95-B:530–5

Deep gluteal syndrome is an increasingly recognized disease entity, caused by compression of the sciatic or pudendal nerve due to non-discogenic pelvic lesions. It includes the piriformis syndrome, the gemelli-obturator internus syndrome, the ischiofemoral impingement syndrome, and the proximal hamstring syndrome. The concept of the deep gluteal syndrome extends our understanding of posterior hip pain due to nerve entrapment beyond the traditional model of the piriformis syndrome. Nevertheless, there has been terminological confusion and the deep gluteal syndrome has often been undiagnosed or mistaken for other conditions. Careful history-taking, a physical examination including provocation tests, an electrodiagnostic study, and imaging are necessary for an accurate diagnosis.

After excluding spinal lesions, MRI scans of the pelvis are helpful in diagnosing deep gluteal syndrome and identifying pathological conditions entrapping the nerves. It can be conservatively treated with multidisciplinary treatment including rest, the avoidance of provoking activities, medication, injections, and physiotherapy.

Endoscopic or open surgical decompression is recommended in patients with persistent or recurrent symptoms after conservative treatment or in those who may have masses compressing the sciatic nerve.

Many physicians remain unfamiliar with this syndrome and there is a lack of relevant literature. This comprehensive review aims to provide the latest information about the epidemiology, aetiology, pathology, clinical features, diagnosis, and treatment.

Cite this article: Bone Joint J 2020;102-B(5):556–567.

The purpose of this study was to determine whether it would be feasible to use oblique lumbar interbody fixation for patients with degenerative lumbar disease who required a fusion but did not have a spondylolisthesis. A series of CT digital images from 60 patients with abdominal disease were reconstructed in three dimensions (3D) using Mimics v10.01: a digital cylinder was superimposed on the reconstructed image to simulate the position of an interbody screw. The optimal entry point of the screw and measurements of its trajectory were recorded. Next, 26 cadaveric specimens were subjected to oblique lumbar interbody fixation on the basis of the measurements derived from the imaging studies. These were then compared with measurements derived directly from the cadaveric vertebrae. Our study suggested that it is easy to insert the screws for L1/2, L2/3 and L3/4 fixation: there was no significant difference in measurements between those of the 3-D digital images and the cadaveric specimens. For L4/5 fixation, part of L5 inferior articular process had to be removed to achieve the optimal trajectory of the screw. For L5/S1 fixation, the screw heads were blocked by iliac bone: consequently, the interior oblique angle of the cadaveric specimens was less than that seen in the 3D digital images. . We suggest that CT scans should be carried out pre-operatively if this procedure is to be adopted in clinical practice. This will assist in determining the feasibility of the procedure and will provide accurate information to assist introduction of the screws. Cite this article: Bone Joint J 2013;95-B:977–82

We investigated the characteristics of patients who achieved Japanese-style deep flexion (seiza-sitting) after total knee replacement (TKR) and measured three-dimensional positioning and the contact positions of the femoral and tibial components. Seiza-sitting was achieved after surgery by 23 patients (29 knees) of a series of 463 TKRs in 341 patients. Pre-operatively most of these patients were capable of seiza-sitting, had a lower body mass index and a favourable attitude towards the Japanese lifestyle (27 of 29 knees). According to two-/three-dimensional image registration analysis in the seiza-sitting position, flexion, varus and internal rotation angles of the tibial component relative to the femoral component had means of 148° (. sd. 8.0), 1.9° (. sd. 3.2) and 13.4° (. sd. 5.9), respectively. Femoral surface contact positions tended to be close to the posterior edge of the tibial polyethylene insert, particularly in the lateral compartment, but only 8.3% (two of 24) of knees showed femoral subluxation over the posterior edge. The mean contact positions of the femoral cam on the tibial post were located 7.8 mm (. sd. 1.5) proximal to the lowest point of the polyethylene surface and 5.5 mm (. sd. 0.9) medial to the centre of the post, indicating that the post-cam contact position translated medially during seiza-sitting, but not proximally. Collectively, the seiza-sitting position seems safe against component dislocation, but the risks of posterior edge loading and breakage of the tibial polyethylene post remain. Cite this article: Bone Joint J 2013;95-B:782–7

Objectives

The aim of this study was to investigate the biomechanical effect of the anterolateral ligament (ALL), anterior cruciate ligament (ACL), or both ALL and ACL on kinematics under dynamic loading conditions using dynamic simulation subject-specific knee models.

Anteversion of the femoral neck of 30 unpaired dry bones was measured directly, by ultrasound, and by computerised tomography. The angles measured directly corresponded well with the angles found by CT scan, but there was poor correlation between these and the angles measured by ultrasound. At present ultrasound seems to be unsuitable for the measurement of anteversion of the femoral neck

This is a prospective randomised study comparing the clinical and radiological outcomes of uni- and bipedicular balloon kyphoplasty for the treatment of osteoporotic vertebral compression fractures. A total of 44 patients were randomised to undergo either uni- or bipedicular balloon kyphoplasty. Self-reported clinical assessment using the Oswestry Disability Index, the Roland-Morris Disability questionnaire and a visual analogue score for pain was undertaken pre-operatively, and at three and twelve months post-operatively. The vertebral height and kyphotic angle were measured from pre- and post-operative radiographs. Total operating time and the incidence of cement leakage was recorded for each group. Both uni- and bipedicular kyphoplasty groups showed significant within-group improvements in all clinical outcomes at three months and twelve months after surgery. However, there were no significant differences between the groups in all clinical and radiological outcomes. Operating time was longer in the bipedicular group (p < 0.001). The incidence of cement leakage was not significantly different in the two groups (p = 0.09). A unipedicular technique yielded similar clinical and radiological outcomes as bipedicular balloon kyphoplasty, while reducing the length of the operation. We therefore encourage the use of a unipedicular approach as the preferred surgical technique for the treatment of osteoporotic vertebral compression fractures. Cite this article: Bone Joint J 2013;95-B:401–6

In developmental dysplasia of the hip (DDH), a bone defect is often observed superior to the acetabulum after the reconstruction at the level of the true acetabulum during total hip replacement (THR). However, the essential amount of uncemented acetabular component coverage required for a satisfactory outcome remains controversial. The purpose of this study was to assess the stability and function of acetabular components with a lack of coverage > 30% (31% to 50%). A total of 760 DDH patients underwent THR with acetabular reconstruction at the level of the true floor. Lack of coverage above the acetabular component of > 30% occurred in 56 patients. Intra-operatively, autogenous morcellised bone grafts were used to fill the uncovered portion. Other than two screws inserted through the acetabular shell, no additional structural supports were used in these hips. In all, four patients were lost to follow-up. Therefore, 52 patients (52 hips, 41 women and 11 men) with a mean age of 60.1 years (42 to 78) were available for this study at a mean of 4.8 years (3 to 7). There were no instances of prosthesis revision or marked loosening during the follow-up. The Harris hip score improved from a mean of 40.7 points (. sd. 12.2) pre-operatively to 91.1 (. sd. 5.0) at the last follow-up. Radiological analysis with medical imaging software allowed us to calculate the extent of the uncoverage in terms of the uncovered arc of the implant as viewed on the anteroposterior pelvic radiograph. From this we propose that up to 17 mm of lateral undercoverage in the presence of a stable initial implantation in the presence of bone autografting, with an inclination angle of the acetabular component between 40° and 55°, is acceptable. This represents undercoverage of ≤ 50%. Cite this article: Bone Joint J 2013;95-B:1178–83

The outcome of high tibial osteotomy (HTO) deteriorates with time, and additional procedures may be required. The aim of this study was to compare the clinical and radiological outcomes between unicompartmental knee replacement (UKR) and total knee replacement (TKR) after HTO as well as after primary UKR. A total of 63 patients (63 knees) were studied retrospectively and divided into three groups: UKR after HTO (group A; n = 22), TKR after HTO (group B; n = 18) and primary UKR (group C; n = 22). The Oxford knee score (OKS), Knee Society score (KSS), hip–knee–ankle angles, mechanical axis and patellar height were evaluated pre- and post-operatively. At a mean of 64 months (19 to 180) post-operatively the mean OKS was 43.8 (33 to 49), 43.3 (30 to 48) and 42.5 (29 to 48) for groups A, B and C, respectively (p = 0.73). The mean KSS knee score was 88.8 (54 to 100), 88.11 (51 to 100) and 85.3 (45 to 100) for groups A, B and C, respectively (p = 0.65), and the mean KSS function score was 85.0 (50 to 100) in group A, 85.8 (20 to 100) in group B and 79.3 (50 to 100) in group C (p = 0.48). Radiologically the results were comparable for all groups except for patellar height, with a higher incidence of patella infra following a previous HTO (p = 0.02). Cite this article: Bone Joint J 2013;95-B:1348–53

Aims

Commonly performed unicompartmental knee arthroplasty (UKA) is not designed for the lateral compartment. Additionally, the anatomical medial and lateral tibial plateaus have asymmetrical geometries, with a slightly dished medial plateau and a convex lateral plateau. Therefore, this study aims to investigate the native knee kinematics with respect to the tibial insert design corresponding to the lateral femoral component.

Aims

Dual plating of distal femoral fractures with medial and lateral implants has been performed to improve construct mechanics and alignment, in cases where isolated lateral plating would be insufficient. This may potentially compromise vascularity, paradoxically impairing healing. This study investigates effects of single versus dual plating on distal femoral vascularity.