This pilot study analysed the outcome of open versus endoscopic curettage and bone grafting for the treatment of simple calcaneal bone cysts. A total of 26 patients were evaluated into two equal groups: group 1 was treated with traditional open curettage and bone grafting and group 2 was treated with endoscopic curettage and percutaneous bone grafting. Cyst size, operating time, length of stay, time to healing, complications, further surgery and radiological healing were recorded and differences were statistically compared.

The mean age of the patients was 22.9 years (18 to 28) and the mean follow-up was 28.7 months (24 to 36). There were no statistically significant differences in regard to age of patients, cyst size and the follow-up periods in the two groups. The operating time and mean length of stay of group 2 patients was significantly shorter than group 1 patients (p <  0.001). The time to healing was similar in the two groups. The overall success rates for groups 1 and 2 were 92.3% (12 of 13) and 100% (13 of 13), respectively, and there were no statistically significant differences regarding radiological healing. This pilot study suggests that endoscopic curettage and percutaneous grafting is a simple and safe form of treatment, with similar results to those following open treatment.

Persistent groin pain after seemingly successful total hip replacement (THR) appears to have become more common. Recent studies have indicated a high incidence after metal-on-polyethylene and metal-on-metal conventional THR and it has been documented in up to 18% of patients after metal-on-metal resurfacing. There are many causes, including acetabular loosening, stress fracture, and iliopsoas tendonitis and impingement. The evaluation of this problem requires a careful history and examination, plain radiographs and an algorithmic approach to special diagnostic imaging and tests. Non-operative treatment is not usually successful. Specific operative treatment depending on the cause of the pain usually involves revision of the acetabular component, iliopsoas tenotomy or other procedures, and is usually successful. Here, an appropriate algorithm is described.

In patients with osteoporosis there is always a strong possibility that pedicle screws will loosen. This makes it difficult to select the appropriate osteoporotic patient for a spinal fusion. The purpose of this study was to determine the correlation between bone mineral density (BMD) and the magnitude of torque required to insert a pedicle screw. To accomplish this, 181 patients with degenerative disease of the lumbar spine were studied prospectively. Each underwent dual-energy x-ray absorptiometry (DEXA) and intra-operative measurement of the torque required to insert each pedicle screw. The levels of torque generated in patients with osteoporosis and osteopenia were significantly lower than those achieved in normal patients. Positive correlations were observed between BMD and T-value at the instrumented lumbar vertebrae, mean BMD and mean T-value of the lumbar vertebrae, and mean BMD and mean T-value of the proximal femur. The predictive torque (Nm) generated during pedicle screw insertion was [-0.127 + 1.62 × (BMD at the corresponding lumbar vertebrae)], as measured by linear regression analysis. The positive correlation between BMD and the maximum torque required to insert a pedicle screw suggests that pre-operative assessment of BMD may be useful in determining the ultimate strength of fixation of a device, as well as the number of levels that need to be fixed with pedicle screws in patients who are suspected of having osteoporosis.

Using a prospective database of 1309 displaced acetabular fractures gathered between 1980 and 2007, we calculated the annual mean age and annual incidence of elderly patients > 60 years of age presenting with these injuries. We compared the clinical details and patterns of fracture between patients > 60 years of age (study group) with those < 60 years (control group). We performed a detailed evaluation of the radiographs of the older group to determine the incidence of radiological characteristics which have been previously described as being associated with a poor patient outcome.

In all, 235 patients were > 60 years of age and the remaining 1074 were < 60 years. The incidence of elderly patients with acetabular fractures increased by 2.4-fold between the first half of the study period and the second half (10% (62) vs 24% (174), p < 0.001). Fractures characterised by displacement of the anterior column were significantly more common in the elderly compared with the younger patients (64% (150) vs 43% (462), respectively, p < 0.001). Common radiological features of the fractures in the study group included a separate quadrilateral-plate component (50.8% (58)) and roof impaction (40% (46)) in the anterior fractures, and comminution (44% (30)) and marginal impaction (38% (26)) in posterior-wall fractures.

The proportion of elderly patients presenting with acetabular fractures increased during the 27-year period. The older patients had a different distribution of fracture pattern than the younger patients, and often had radiological features which have been shown in other studies to be predictive of a poor outcome.

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.

Lately, concerns have arisen following the use of large metal-on-metal bearings in hip replacements owing to reports of catastrophic soft-tissue reactions resulting in implant failure and associated complications. This review examines the literature and contemporary presentations on current clinical dilemmas in metal-on-metal hip replacement.

A 70-year-old man with an uncemented metal-on-polyethylene total hip prosthesis underwent revision arthroplasty 33 months later because of pain, swelling and recurrent dislocation. There appeared to be corrosion and metal release from the prosthetic head, resulting in pseudotumour formation and severe local soft-tissue destruction. The corrosion occurred at the junction between the titanium-molybdenum-zirconium-iron taper and the cobalt-chrome-molybdenum head, but the mechanism was unproven.

Over recent years hip arthroscopic surgery has evolved into one of the most rapidly expanding fields in orthopaedic surgery. Complications are largely transient and incidences between 0.5% and 6.4% have been reported. However, major complications can and do occur. This article analyses the reported complications and makes recommendations based on the literature review and personal experience on how to minimise them.

We have reviewed five adult patients treated with endoprosthetic reconstruction of the proximal radius following resection of non-traumatic lesions. The patients had a mean age of 33.4 years (20 to 60) at the time of surgery and the mean follow-up was 7.6 years (0.8 to 16).

Following surgery, all elbows were clinically stable and there was 100% survivorship of the prosthesis. Evaluation of function was assessed clinically and by the Mayo Elbow Performance Score, achieving a mean of 86% (70 to 100).

Results at medium-term follow-up are encouraging with regards to elbow stability, implant survivorship and functional outcome.

Robots have been used in surgery since the late 1980s. Orthopaedic surgery began to incorporate robotic technology in 1992, with the introduction of ROBODOC, for the planning and performance of total hip replacement. The use of robotic systems has subsequently increased, with promising short-term radiological outcomes when compared with traditional orthopaedic procedures. Robotic systems can be classified into two categories: autonomous and haptic (or surgeon-guided). Passive surgery systems, which represent a third type of technology, have also been adopted recently by orthopaedic surgeons.

While autonomous systems have fallen out of favour, tactile systems with technological improvements have become widely used. Specifically, the use of tactile and passive robotic systems in unicompartmental knee replacement (UKR) has addressed some of the historical mechanisms of failure of non-robotic UKR. These systems assist with increasing the accuracy of the alignment of the components and produce more consistent ligament balance. Short-term improvements in clinical and radiological outcomes have increased the popularity of robot-assisted UKR.

Robot-assisted orthopaedic surgery has the potential for improving surgical outcomes. We discuss the different types of robotic systems available for use in orthopaedics and consider the indication, contraindications and limitations of these technologies.

We reviewed the outcome of a retrospective case series of eight patients with atlantoaxial instability who had been treated by percutaneous anterior transarticular screw fixation and grafting under image-intensifier guidance between December 2005 and June 2008.

The mean follow-up was 19 months (8 to 27). All eight patients had a solid C1–2 fusion. There were no breakages or displacement of screws. All the patients with pre-operative neck pain had immediate relief from their symptoms or considerable improvement. There were no major complications. Our preliminary clinical results suggest that percutaneous anterior transarticulation screw fixation is technically feasible, safe, useful and minimally invasive when using the appropriate instruments allied to intra-operative image intensification, and by selecting the correct puncture point, angle and depth of insertion.

Between 1999 and 2001, 90 patients underwent total hip replacement using the same uncemented acetabular and femoral components with a 28 mm metallic femoral head but with prospective randomisation of the acetabular liner to either Durasul highly cross-linked polyethylene or nitrogen-sterilised Sulene polyethylene. We assessed 83 patients at a minimum follow-up of ten years. Linear penetration of the femoral head was estimated at six weeks, six and 12 months and annually thereafter, using the Dorr method, given the non-spherical shape of the acetabular component.

There was no loosening of any component; only one hip in the Sulene group showed proximal femoral osteolysis. The mean penetration of the femoral head at six weeks was 0.08 mm (0.02 to 0.15) for the Durasul group and 0.16 mm (0.05 to 0.28) for the Sulene group (p = 0.001). The mean yearly linear penetration was 64.8% lower for the Durasul group at 0.05 mm/year (sd 0.035) for the Sulene group and 0.02 mm/year (sd 0.016) for the Durasul (p < 0.001). Mean linear femoral head penetration at ten years was 61% less in the Durasul than Sulene group. Highly cross-linked polyethylene gives excellent results at ten years.

Cite this article: Bone Joint J 2013;95-B:326–32.

There is conflicting evidence about the merits of mobile bearings in total knee replacement, partly because most randomised controlled trials (RCTs) have not been adequately powered. We report the results of a multicentre RCT of mobile versus fixed bearings. This was part of the knee arthroplasty trial (KAT), where 539 patients were randomly allocated to mobile or fixed bearings and analysed on an intention-to-treat basis. The primary outcome measure was the Oxford Knee Score (OKS) plus secondary measures including Short Form-12, EuroQol EQ-5D, costs, cost-effectiveness and need for further surgery.

There was no significant difference between the groups pre-operatively: mean OKS was 17.18 (sd 7.60) in the mobile-bearing group and 16.49 (sd 7.40) in the fixed-bearing group. At five years mean OKS was 33.19 (sd 16.68) and 33.65 (sd 9.68), respectively. There was no significant difference between trial groups in OKS at five years (-1.12 (95% confidence interval -2.77 to 0.52) or any of the other outcome measures. Furthermore, there was no significant difference in the proportion of patients with knee-related re-operations or in total costs.

In this appropriately powered RCT, over the first five years after total knee replacement functional outcomes, re-operation rates and healthcare costs appear to be the same irrespective of whether a mobile or fixed bearing is used.

Cite this article: Bone Joint J 2013;95-B:486–92.

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.

The February 2013 Spine Roundup³⁶⁰ looks at: complications with anterior decompression and fusion; lumbar claudication and peripheral vascular disease; increasing cervical instability in rheumatoids; kyphoplasty; cervical stenosis; exercise or fusion for chronic lower back pain; lumbar disc arthroplasty and adjacent level changes; and obese disc prolapses.

Rupture of an aneurysm of the common iliac artery is a rare cause of pain in the hip. We describe an elderly hypertensive patient with an aneurysmal rupture of the left common iliac artery who presented with unilateral hip pain masquerading as septic arthritis.

We describe 22 cases of bizarre parosteal osteochondromatous proliferation, or Nora’s lesion. These are surface-based osteocartilaginous lesions typically affecting the hands and feet. All patients were identified from the records of a regional bone tumour unit and were treated between 1985 and 2009. Nine lesions involved the metacarpals, seven the metatarsals, one originated from a sesamoid bone of the foot and five from long bones (radius, ulna, tibia, and femur in two). The mean age of the patients was 31.8 years (6 to 66), with 14 men and eight women. Diagnosis was based on the radiological and histological features. The initial surgical treatment was excision in 21 cases and amputation of a toe in one. The mean follow-up was for 32 months (12 to 162). Recurrence occurred in six patients (27.3%), with a mean time to recurrence of 49 months (10 to 120). Two of the eight patients with complete resection margins developed a recurrence (25.0%), compared with four of 14 with a marginal or incomplete resection (28.6%).

Given the potential surgical morbidity inherent in resection, our data suggest that there may be a role for a relatively tissue-conserving approach to the excision of these lesions.

The most common injury in rugby resulting in spinal cord injury (SCI) is cervical facet dislocation. We report on the outcome of a series of 57 patients with acute SCI and facet dislocation sustained when playing rugby and treated by reduction between 1988 and 2000 in Conradie Hospital, Cape Town. A total of 32 patients were completely paralysed at the time of reduction. Of these 32, eight were reduced within four hours of injury and five of them made a full recovery. Of the remaining 24 who were reduced after four hours of injury, none made a full recovery and only one made a partial recovery that was useful. Our results suggest that low-velocity trauma causing SCI, such as might occur in a rugby accident, presents an opportunity for secondary prevention of permanent SCI. In these cases the permanent damage appears to result from secondary injury, rather than primary mechanical spinal cord damage. In common with other central nervous system injuries where ischaemia determines the outcome, the time from injury to reduction, and hence reperfusion, is probably important.

In order to prevent permanent neurological damage after rugby injuries, cervical facet dislocations should probably be reduced within four hours of injury.

Interfacial defects between the cement mantle and a hip implant may arise from constrained shrinkage of the cement or from air introduced during insertion of the stem. Shrinkage-induced interfacial porosity consists of small pores randomly located around the stem, whereas introduced interfacial gaps are large, individual and less uniformly distributed areas of stem-cement separation. Using a validated CT-based technique, we investigated the extent, morphology and distribution of interfacial gaps for two types of stem, the Charnley-Kerboul and the Lubinus SPII, and for two techniques of implantation, line-to-line and undersized.

The interfacial gaps were variable and involved a mean of 6.43% (sd 8.99) of the surface of the stem. Neither the type of implant nor the technique of implantation had a significant effect on the regions of the gaps, which occurred more often over the flat areas of the implant than along the corners of the stems, and were more common proximally than distally for Charnley-Kerboul stems cemented line-to-line. Interfacial defects could have a major effect on the stability and survival of the implant.

The sternoclavicular joint is vulnerable to the same disease processes as other synovial joints, the most common of which are instability from injury, osteoarthritis, infection and rheumatoid disease. Patients may also present with other conditions, which are unique to the joint, or are manifestations of a systemic disease process. The surgeon should be aware of these possibilities when assessing a patient with a painful, swollen sternoclavicular joint.