The December 2013 Spine Roundup³⁶⁰ looks at: Just how common is lumbar spinal stenosis?; How much will they bleed?; C5 palsy associated with stenosis; Atlanto-axial dislocations revisited; 3D predictors of progression in scoliosis; No difference in outcomes by surgical approach for fusion; Cervical balance changes after thoracolumbar surgery; and spinal surgeons first in space.

In an initial randomised controlled trial (RCT) we segregated 180 patients to one of two knee positions following total knee replacement (TKR): six hours of knee flexion using either a jig or knee extension. Outcome measures included post-operative blood loss, fall in haemoglobin, blood transfusion requirements, knee range of movement, limb swelling and functional scores. A second RCT consisted of 420 TKR patients randomised to one of three post-operative knee positions: flexion for three or six hours post-operatively, or knee extension.

Positioning of the knee in flexion for six hours immediately after surgery significantly reduced blood loss (p = 0.002). There were no significant differences in post-operative range of movement, swelling, pain or outcome scores between the various knee positions in either study. Post-operative knee flexion may offer a simple and cost-effective way to reduce blood loss and transfusion requirements following TKR.

We also report a cautionary note regarding the potential risks of prolonged knee flexion for more than six hours observed during clinical practice in the intervening period between the two trials, with 14 of 289 patients (4.7%) reporting lower limb sensory neuropathy at their three-month review.

Cite this article: Bone Joint J 2014;96-B:201–9.

The December 2013 Children’s orthopaedics Roundup³⁶⁰ looks at: Long term-changes in hip morphology following osteotomy; Arthrogrypotic wrist contractures are surgically amenable; Paediatric femoral lengthening over a nail; Current management of paediatric supracondylar fractures; MRI perfusion index predictive of Perthes’ progression; Abduction bracing effective in residual acetabular deformity; Hurler syndrome in the spotlight; and the Pavlik works for femoral fractures too!

Pre-operative planning for total hip replacement (THR) is challenging in hips with severe acetabular deformities, including those with a hypoplastic acetabulum or severe defects and in the presence of arthrodesis or ankylosis. We evaluated whether a Rapid Prototype (RP) model, which is a life-sized reproduction based on three-dimensional CT scans, can determine the feasibility of THR and provide information about the size and position of the acetabular component in severe acetabular deformities. THR was planned using an RP model in 21 complex hips in five men (five hips) and 16 women (16 hips) with a mean age of 47.7 years (24 to 70) at operation. An acetabular component was implanted successfully and THR completed in all hips. The acetabular component used was within 2 mm of the predicted size in 17 hips (80.9%). All of the acetabular components and femoral stems had radiological evidence of bone ingrowth and stability at the final follow-up, without any detectable wear or peri-prosthetic osteolysis. The RP model allowed a simulated procedure pre-operatively and was helpful in determining the feasibility of THR pre-operatively, and to decide on implant type, size and position in complex THRs.

Cite this article: Bone Joint J 2013;95-B:1458–63.

Eighteen hip fusions were converted to total hip replacements. A constrained acetabular liner was used in three hips. Mean follow up was five years (two to 15). Two (11%) hips failed, requiring revision surgery and two patients (11%) had injury to the peroneal nerve. Heterotopic ossification developed in seven (39%) hips, in one case resulting in joint ankylosis. No hips dislocated.

Conversion of hip fusion to hip replacement carries an increased risk of heterotopic ossification and neurological injury. We advise prophylaxis against heterotropic ossification. When there is concern about hip stability we suggest that the use of a constrained acetabular liner is considered. Despite the potential for complications, this procedure had a high success rate and was effective in restoring hip function.

A consecutive series of 320 patients with an intracapsular fracture of the hip treated with a dynamic locking plate (Targon Femoral Neck (TFN)) were reviewed. All surviving patients were followed for a minimum of two years. During the follow-up period 109 patients died.

There were 112 undisplaced fractures, of which three (2.7%) developed nonunion or re-displacement and five (4.5%) developed avascular necrosis of the femoral head. Revision to an arthroplasty was required for five patients (4.5%). A further six patients (5.4%) had elective removal of the plate and screws.

There were 208 displaced fractures, of which 32 (15.4%) developed nonunion or re-displacement and 23 (11.1%) developed avascular necrosis. A further four patients (1.9%) developed a secondary fracture around the TFN. Revision to a hip replacement was required for 43 patients (20.7%) patients and a further seven (3.3%) had elective removal of the plate and screws.

It is suggested that the stronger distal fixation combined with rotational stability may lead to a reduced incidence of complications related to the healing of the fracture when compared with other contemporary fixation devices but this needs to be confirmed in further studies.

Cite this article: Bone Joint J 2013;95-B:1402–5.

While the demand for orthopaedic surgical expertise in the developing world is in critically short supply, short-term remedy from visiting doctors cannot solve this long-term healthcare problem. Capacity building by senior and training orthopaedic surgeons from established Western training programmes can offer a significant contribution to the orthopaedic patient in the developing world and the gains for those visiting are extremely valuable. We report on several visits by a UK orthopaedic team to a hospital in Kabul, Afghanistan and discuss the operative and non-operative case mix and the benefits in terms of local capacity building and the unique experience of those visiting.

A total of 187 patients with primary osteoarthritis (OA) of the knee undergoing total knee replacement (TKR) were randomly divided into two groups, one of which underwent synovectomy. The patients and assessors were blinded to the randomisation both before and after surgery. The duration of surgery, hospitalisation period, concealed bleeding, drainage volume, blood transfusion rate and range of movement of the knee at three days after the operation were analysed. Patients were followed up at four weeks and 12 months after their operation, and a visual analogue score (VAS) for pain, Knee Society score (KSS) and a patellar ballottement test were compared between the groups.

The mean amount of concealed bleeding was higher in the synovectomy group compared with the control group (1.24 l (0.08 to 3.28) vs 1.03 l (0.16 to 2.94); p = 0.042), as was the mean drainage volume (0.90 l (0.35 to 1.81) vs 0.81 (0.25 to 1.65); p = 0.030). The mean operating time was also higher in the synovectomy group compared with the controls (1.50 hours (1.34 to 1.75) vs 1.41 hours (1.21 to 1.79); p = 0.006). There were no significant differences in blood transfusion rate (p = 0.882), hospital stay (p = 0.805) or range of movement of the knee (p = 0.413) between the two groups. At four weeks and 12 months post-operatively there were no statistically significant differences in any of the measured parameters. We concluded that synovectomy confers no clinical advantages in TKR for primary OA while subjecting patients to higher levels of bleeding and longer operating times.

Cite this article: Bone Joint J 2013;95-B:1197–200.

As it remains unproven that hypermobility of the first tarsometatarsal joint (TMTJ-1) is a significant factor in hallux valgus deformity, the necessity for including arthrodesis of TMTJ-1 as part of a surgical correction of a hallux valgus is questionable. In order to evaluate the role of this arthrodesis on the long-term outcome of hallux valgus surgery, a prospective, blinded, randomised study with long-term follow-up was performed, comparing the Lapidus procedure (which includes such an arthrodesis) with a simple Hohmann distal closing wedge metatarsal osteotomy. The study cohort comprised 101 feet in 87 patients: 50 feet were treated with a Hohmann procedure and 51 with a Lapidus procedure. Hypermobility of TMTJ-1 was assessed pre-operatively by clinical examination. After a mean of 9.25 years (7.25 to 11.42), 91 feet in 77 patients were available for follow-up. There was no difference in clinical or radiological outcome between the two procedures. Also, there was no difference in outcome between the two procedures in the subgroup clinically assessed as hypermobile. This study does not support the theory that a hallux valgus deformity in a patient with a clinically assessed hypermobile TMTJ-1 joint requires fusion of the first tarso-metatarsal joint.

Cite this article: Bone Joint J 2013;95-B:1222–6.

Although it has been suggested that the outcome after revision of a unicondylar knee replacement (UKR) to total knee replacement (TKR) is better when the mechanism of failure is understood, a comparative study on this subject has not been undertaken.

A total of 30 patients (30 knees) who underwent revision of their unsatisfactory UKR to TKR were included in the study: 15 patients with unexplained pain comprised group A and 15 patients with a defined cause for pain formed group B. The Oxford knee score (OKS), visual analogue scale for pain (VAS) and patient satisfaction were assessed before revision and at one year after revision, and compared between the groups.

The mean OKS improved from 19 (10 to 30) to 25 (11 to 41) in group A and from 23 (11 to 45) to 38 (20 to 48) in group B. The mean VAS improved from 7.7 (5 to 10) to 5.4 (1 to 8) in group A and from 7.4 (2 to 9) to 1.7 (0 to 8) in group B. There was a statistically significant difference between the mean improvements in each group for both OKS (p = 0.022) and VAS (p = 0.002). Subgroup analysis in group A, performed in order to define a patient factor that predicts outcome of revision surgery in patients with unexplained pain, showed no pre-operative differences between both subgroups.

These results may be used to inform patients about what to expect from revision surgery, highlighting that revision of UKR to TKR for unexplained pain generally results in a less favourable outcome than revision for a known cause of pain.

Cite this article: Bone Joint J 2013;95-B:1204–8.

Although the importance of lateral femoral wall integrity is increasingly being recognised in the treatment of intertrochanteric fracture, little attention has been put on the development of a secondary post-operative fracture of the lateral wall. Patients with post-operative fractures of the lateral wall were reported to have high rates of re-operation and complication. To date, no predictors of post-operative lateral wall fracture have been reported. In this study, we investigated the reliability of lateral wall thickness as a predictor of lateral wall fracture after dynamic hip screw (DHS) implantation.

A total of 208 patients with AO/OTA 31-A1 and -A2 classified intertrochanteric fractures who received internal fixation with a DHS between January 2003 and May 2012 were reviewed. There were 103 men and 150 women with a mean age at operation of 78 years (33 to 94). The mean follow-up was 23 months (6 to 83). The right side was affected in 97 patients and the left side in 111. Clinical information including age, gender, side, fracture classification, tip–apex distance, follow-up time, lateral wall thickness and outcome were recorded and used in the statistical analysis.

Fracture classification and lateral wall thickness significantly contributed to post-operative lateral wall fracture (both p < 0.001). The lateral wall thickness threshold value for risk of developing a secondary lateral wall fracture was found to be 20.5 mm.

To our knowledge, this is the first study to investigate the risk factors of post-operative lateral wall fracture in intertrochanteric fracture. We found that lateral wall thickness was a reliable predictor of post-operative lateral wall fracture and conclude that intertrochanteric fractures with a lateral wall thickness < 20.5 mm should not be treated with DHS alone.

Cite this article: Bone Joint J 2013;95-B:1134–8.

We tested four types of surgical repair for load to failure and distraction in a bovine model of Achilles tendon repair. A total of 20 fresh bovine Achilles tendons were divided transversely 4 cm proximal to the calcaneal insertion and randomly repaired using the Dresden technique, a Krackow suture, a triple-strand Dresden technique or a modified oblique Dresden technique, all using a Fiberwire suture. Each tendon was loaded to failure. The force applied when a 5 mm gap was formed, peak load to failure, and mechanism of failure were recorded. The resistance to distraction was significantly greater for the triple technique (mean 246.1 N (205 to 309) to initial gapping) than for the Dresden (mean 180 N (152 to 208); p = 0.012) and the Krackow repairs (mean 101 N (78 to 112; p < 0.001). Peak load to failure was significantly greater for the triple-strand repair (mean 675 N (453 to 749)) than for the Dresden (mean 327.8 N (238 to 406); p < 0.001), Krackow (mean 223.6 N (210 to 252); p <  0.001) and oblique repairs (mean 437.2 N (372 to 526); p < 0.001). Failure of the tendon was the mechanism of failure for all specimens except for the tendons sutured using the Krackow technique, where the failure occurred at the knot.

The triple-strand technique significantly increased the tensile strength (p = 0.0001) and gap resistance (p = 0.01) of bovine tendon repairs, and might have advantages in human application for accelerated post-operative rehabilitation.

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

We aimed to further evaluate the biomechanical characteristics of two locking screws versus three standard bicortical screws in synthetic models of normal and osteoporotic bone.

We present the extended follow-up (≥ 20 years) of a series of fully hydroxyapatite-coated femoral components used in 72 primary total hip replacements (THRs). Earlier results of this cohort have been previously published. All procedures were performed between 1986 and 1991. The series involved 45 women and 15 men with 12 bilateral procedures. Their mean age at the time of surgery was 60 years (46 to 80) and the mean duration of follow-up was 22.5 years (20 to 25). At final follow-up, the mean Merle d’Aubigné and Postel hip scores were 5.5 (4.5 to 6), 3.8 (3.5 to 5) and 3.3 (3.0 to 5.0) for pain, mobility and function, respectively. Of the patients 92% were very satisfied at the time of final follow-up.

There were seven revisions: six of the acetabular component for aseptic loosening and one of both the stem and the acetabular component for loosening due to deep infection. The survival of this prosthesis at 22.5 years with revision for any reason as the endpoint was 91.7% (95% confidence interval (CI) 84 to 99). Survival with aseptic loosening of the stem as the endpoint was 100% (95% CI 90 to 100).

This prosthesis provides pain relief in the long term. Survival of this component is comparable to the best results for primary THR with any means of fixation.

Cite this article: Bone Joint J 2013;95-B:467–71.

It is important to be able to identify patients with an increased risk of venous thromboembolism (VTE) in order to minimise the risk of an event. We investigated the incidence and risk factors for post-operative VTE in 168 consecutive patients with a malignancy of the lower limb. The period of study included ten months before and 12 months after the introduction of chemical thromboprophylaxis. All data about the potential risk factors were identified and classified into three groups (patient-, surgery- and tumour-related). The outcome measure was a thromboembolic event within 90 days of surgery.

Of the 168 patients, eight (4.8%) had a confirmed symptomatic deep-vein thrombosis and one (0.6%) a fatal pulmonary embolism. Of the 28 variables tested, age > 60 years, higher American Society of Anesthesiologists grade and metastatic tumour were independent risk factors for VTE. The overall rate of symptomatic VTE was not significantly different between patients who received chemical thromboprophylaxis and those who did not. Knowledge of these risk factors may be of value in improving the surgical outcome of patients with a malignancy of the lower limb.

Cite this article: Bone Joint J 2013;95-B:558–62.

Severe hallux valgus deformity is conventionally treated with proximal metatarsal osteotomy. Distal metatarsal osteotomy with an associated soft-tissue procedure can also be used in moderate to severe deformity. We compared the clinical and radiological outcomes of proximal and distal chevron osteotomy in severe hallux valgus deformity with a soft-tissue release in both. A total of 110 consecutive female patients (110 feet) were included in a prospective randomised controlled study. A total of 56 patients underwent a proximal procedure and 54 a distal operation. The mean follow-up was 39 months (24 to 54) in the proximal group and 38 months (24 to 52) in the distal group. At follow-up the hallux valgus angle, intermetatarsal angle, distal metatarsal articular angle, tibial sesamoid position, American Orthopaedic Foot and Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal score, patient satisfaction level, and complications were similar in each group. Both methods showed significant post-operative improvement and high levels of patient satisfaction. Our results suggest that the distal chevron osteotomy with an associated distal soft-tissue procedure provides a satisfactory method for correcting severe hallux valgus deformity.

Cite this article: Bone Joint J 2013;95-B:510–16.

We present our experience of the modified Dunn procedure in combination with a Ganz surgical dislocation of the hip to treat patients with severe slipped capital femoral epiphysis (SCFE). The aim was to prospectively investigate whether this technique is safe and reproducible. We assessed the degree of reduction, functional outcome, rate of complications, radiological changes and range of movement in the hip. There were 28 patients with a mean follow-up of 38.6 months (24 to 84). The lateral slip angle was corrected by a mean of 50.9° (95% confidence interval 44.3 to 57.5). The mean modified Harris hip score at the final follow-up was 89.1 (sd 9.0) and the mean Non-Arthritic Hip score was 91.3 (sd 9.0). Two patients had proven pre-existing avascular necrosis and two developed the condition post-operatively. There were no cases of nonunion, implant failure, infection, deep-vein thrombosis or heterotopic ossification. The range of movement at final follow-up was nearly normal. This study adds to the evidence that the technique of surgical dislocation and anatomical reduction is safe and reliable in patients with SCFE.

Cite this article: Bone Joint J 2013;95-B:424–9.

Femoroacetabular impingement (FAI) is commonly associated with early hip arthritis. We reviewed our series of 1300 hip resurfacing procedures. More than 90% of our male patients, with an average age of 53 years, had cam impingement lesions. In this condition, there are anterior femoral neck osteophytes, and a retroverted femoral head on a normally anteverted neck. It is postulated that FAI results in collision of the anterior neck of the femur against the rim of the acetabulum, causing damage to the acetabular labrum and articular cartilage, resulting in osteoarthritis. Early treatment of FAI involves arthroscopic or open removal of bone from the anterior femoral neck, as well as repair or removal of labral tears. However, once osteoarthritis has developed, hip replacement or hip resurfacing is indicated. Hip resurfacing can re-orient the head and re-shape the neck. This helps to restore normal biomechanics to the hip, eliminate FAI, and improve range of motion. Since many younger men with hip arthritis have FAI, and are also considered the best candidates for hip resurfacing, it is evident that resurfacing has a role in these patients.

We reviewed the outcome of distal chevron metatarsal osteotomy without tendon transfer in 19 consecutive patients (19 feet) with a hallux varus deformity following surgery for hallux valgus. All patients underwent distal chevron metatarsal osteotomy with medial displacement and a medial closing wedge osteotomy along with a medial capsular release.

The mean hallux valgus angle improved from −11.6° pre-operatively to 4.7° postoperatively, the mean first-second intermetatarsal angle improved from −0.3° to 3.3° and the distal metatarsal articular angle from 9.5° to 2.3° and the first metatarsophalangeal joints became congruent post-operatively in all 19 feet. The mean relative length ratio of the metatarsus decreased from 1.01 to 0.99 and the mean American Orthopaedic Foot and Ankle Society score improved from 77 to 95 points.

In two patients the hallux varus recurred. One was symptom-free but the other remained symptomatic after a repeat distal chevron osteotomy. There were no other complications.

We consider that distal chevron metatarsal osteotomy with a medial wedge osteotomy and medial capsular release is a useful procedure for the correction of hallux varus after surgery for hallux valgus.