Aims

We conducted a randomised controlled trial to assess the accuracy of positioning and alignment of the components in total knee arthroplasty (TKA), comparing those undertaken using standard intramedullary cutting jigs and those with patient-specific instruments (PSI).

The piriformis muscle is an important landmark in the surgical anatomy of the hip, particularly the posterior approach for total hip replacement (THR). Standard orthopaedic teaching dictates that the tendon must be cut in to allow adequate access to the superior part of the acetabulum and the femoral medullary canal. However, in our experience a routine THR can be performed through a posterior approach without sacrificing this tendon.

We dissected the proximal femora of 15 cadavers in order to clarify the morphological anatomy of the piriformis tendon. We confirmed that the tendon attaches on the crest of the greater trochanter, in a position superior to the trochanteric fossa, away from the entry point for broaching the intramedullary canal during THR. The tendon attachment site encompassed the summit and medial aspect of the greater trochanter as well as a variable attachment to the fibrous capsule of the hip joint. In addition we dissected seven cadavers resecting all posterior attachments except the piriformis muscle and tendon in order to study their relations to the hip joint, as the joint was flexed. At flexion of 90° the piriformis muscle lay directly posterior to the hip joint.

The piriform fossa is a term used by orthopaedic surgeons to refer the trochanteric fossa and normally has no relation to the attachment site of the piriformis tendon. In hip flexion the piriformis lies directly behind the hip joint and might reasonably be considered to contribute to the stability of the joint.

We conclude that the anatomy of the piriformis muscle is often inaccurately described in the current surgical literature and terms are used and interchanged inappropriately.

Cite this article: Bone Joint J 2013;95-B:764–9.

We undertook a randomised controlled trial to compare the piriformis-sparing approach with the standard posterior approach used for total hip replacement (THR). We recruited 100 patients awaiting THR and randomly allocated them to either the piriformis-sparing approach or the standard posterior approach. Pre- and post-operative care programmes and rehabilitation regimes were identical for both groups. Observers were blinded to the allocation throughout; patients were blinded until the two-week assessment. Follow-up was at six weeks, three months, one year and two years. In all 11 patients died or were lost to follow-up.

There was no significant difference between groups for any of the functional outcomes. However, for patients in the piriformis-sparing group there was a trend towards a better six-minute walk test at two weeks and greater patient satisfaction at six weeks. The acetabular components were less anteverted (p = 0.005) and had a lower mean inclination angle (p = 0.02) in the piriformis-sparing group. However, in both groups the mean component positions were within Lewinnek’s safe zone. Surgeons perceived the piriformis-sparing approach to be significantly more difficult than the standard approach (p = 0.03), particularly in obese patients.

In conclusion, performing THR through a shorter incision involving sparing piriformis is more difficult and only provides short-term benefits compared with the standard posterior approach.

Objectives: To compare the results of various surgical approaches to the knee in primary arthroplasty surgery.

Design: Systematic review with meta-analysis

Data Sources: Cochrane Bone, Joint, and Muscle Trauma group trials register (2007), Cochrane central register of controlled trials (Cochrane Library issue 2, 2007), Medline (1950 to February 2007), Embase (1974 to February 2007), CINAHL (1982 to February 2007), Pubmed, SCOPUS and ZETOC. If data was insufficient trialists were contacted via telephone, email or letter.

Review methods: Randomised and quasi-randomised controlled trials comparing surgical approaches to the knee in patients undergoing primary arthroplasty surgery.

Results: Twenty-three randomised, controlled trials (1282 patients, 1490 TKAs) were included.

Midvastus vs Medial Parapatellar approach: Quadriceps function in the early post operative period was better preserved in the MV group. Post operative pain, blood loss and the need for LRR tended to be lower in the MV group. There was no difference in ROM, hospital stay, knee scores, complications or radiological alignment.

Conclusions: Approaches preserving the quadriceps tendon improve the early extensor mechanism function and tend to decrease the need for LRR. Combined with a decrease blood loss and postoperative pain, these approaches improve early rehabilitation and allow for a more rapid recovery of knee function. However, these early improvements fail to provide any long term benefit, do not improve knee scores, or decrease the length of hospital stay.

Introduction: With the rising number of primary hip arthroplasties performed each year, patient selection criteria is becoming increasingly pertinent. There is growing concern that patients with a high body mass index (BMI) have worse outcomes following hip replacement surgery. However the evidence base is equivocal.

Our aim is to assess whether BMI has an impact on clinical and radiological outcomes of primary total hip arthroplasties

Methods: This is a prospective study of 92 patients, undergoing primary total hip arthroplasty, recruited from two hospitals. Data was collected by the operating surgical team and independent physiotherapists at the preoperative assessment clinic, intraoperatively and at six weeks post-operative follow up.

BMI was recorded. Patients were divided into 2 groups: those with a BMI less than 30 (considered nonobese) and those 30 or above (obese).

Outcomes assessed included blood loss and requirement blood transfusion, fat thickness, operation duration, complications and surgeon’s perception of the difficulty of operation (scored on a VAS). In addition functional capacity was assessed using the Oxford Hip scores pre and post-operatively. Radiographs were scored independently according to Dorr and Barrack.

Results: Of our 92 patients, 36 were obese and 56 were non-obese. There was no significant difference found in blood loss, blood transfusion requirements, operation duration and complications between the two groups, With regards to the Oxford Hip scores, the obese patients had greater differences between their pre- and post-operative scores but this difference was not significant (p=0.09). We found a significant difference (p=0.003) in surgeons’ perception of the difficulty of operation with VAS scores for obese patients being higher than non-obese patients. Our Dorr and Barrack scores revealed no significant difference in radiological outcome between our two groups.

Conclusion: Our study would suggest that obese patients do not have worse outcomes following primary total hip arthroplasty than non-obese patients.

We treated 34 patients with recurrent dislocation of the hip with a constrained acetabular component. Roentgen stereophotogrammetric analysis was performed to assess migration of the prosthesis.

The mean clinical follow-up was 3.0 years (2.2 to 4.8) and the radiological follow-up was 2.7 years (2.0 to 4.8). At the latest review six patients had died and none was lost to follow-up. There were four acetabular revisions, three for aseptic loosening and one for deep infection. Another acetabular component was radiologically loose with progressive radiolucent lines in all Gruen zones and was awaiting revision. The overall rate of aseptic loosening was 11.8% (4 of 34). Roentgen stereophotogrammetric analysis in the non-revised components confirmed migration of up to 1.06 mm of translation and 2.32° of rotation at 24 months. There was one case of dislocation and dissociation of the component in the same patient. Of the 34 patients, 33 (97.1%) had no further episodes of dislocation.

The constrained acetabular component reported in our study was effective in all but one patient with instability of the hip, but the rate of aseptic loosening was higher than has been reported previously and requires further investigation.

We carried out a blinded prospective randomised controlled trial comparing 2-octylcyanoacrylate (OCA), subcuticular suture (monocryl) and skin staples for skin closure following total hip and total knee arthroplasty. We included 102 hip replacements and 85 of the knee.

OCA was associated with less wound discharge in the first 24 hours for both the hip and the knee. However, with total knee replacement there was a trend for a more prolonged wound discharge with OCA. With total hip replacement there was no significant difference between the groups for either early or late complications. Closure of the wound with skin staples was significantly faster than with OCA or suture. There was no significant difference in the length of stay in hospital, Hollander wound evaluation score (cosmesis) or patient satisfaction between the groups at six weeks for either hips or knees.

We consider that skin staples are the skin closure of choice for both hip and knee replacements.

Study Design: A prospective randomised controlled trial.

Objective: The early management of acute soft tissue injuries of the neck remains controversial. The aim of this study was to compare an early mobilisation regime versus with treatment with a soft collar for recovery of function and activity levels after soft tissue injuries of the neck.

Subjects: Over a one year period, 108 patients presenting with a soft tissue neck injury were enrolled in a prospective trial. Each patient was randomised to either early mobilisation using an exercise regime (55 patients) or 3 weeks treatment in a soft collar followed by the same exercise regime (53 patients). Patients were followed up at 3, 12 and 52 week intervals from injury.

Outcome Measures: Visual Analogue Scores for pain, range of neck movements, activities of daily living and time taken to return to work.

Results: No differences were found between the two groups for pain, range of neck movements or for activities of daily living at any of the follow up intervals. The collar treatment group took significantly longer to return to work after injury (21 days) compared to the early mobilisation group (9 days), p< 0.05.

Conclusions: Treatment in a soft collar had no clinical benefit compared to early mobilisation in terms of recovery of function, pain or range of neck movements, but was associated with an increased time to return to work.

The best management of displaced intracapsular femoral neck fractures in the elderly remains undecided. Most are treated by hemiarthroplasty. The aim of this study was to establish whether the advantages of cement outweigh the disadvantages.

All patients with displaced intracapsular femoral neck fractures treated with herniarthroplasty between January 1997 and May 1998, in 2 hospitals within the same Deanery, were reviewed. The same prosthesis was used, but in hospital A they were uncemented, and in B cemented. There were 122 patients in hospital A and 123 in B. We conducted a detailed retrospective analysis of hospital notes. All surviving patients (50 and 56 respectively) were interviewed to obtain pre-fracture and current scores of pain, walking ability, use of walking aids, activities of daily living (ADL) and accommodation status, using validated scoring systems. The relative deterioration over the follow-up period (32–36 months) was determined and the groups compared.

Patient demographics confirmed comparability of groups. There was no greater incidence of intra-operative fall in diastolic blood pressure, or oxygen saturation in the cemented group. Cemented procedures were on average 15 minutes longer. Median in-patient stay was the same. Significantly fewer of the cemented group had been revised or were awaiting revision (p=0. 036). There was no difference in mortality rates at any point between surgery and follow-up. Prospective assessment of surviving patients revealed highly statistically significant greater deterioration in pain (p=0. 003), walking ability (p=0. 002), use of walking aids (p=0. 003) and ADL (p=0. 009) in the uncemented group. The trend for more dependent accommodation in the uncemented group failed to reach statistical significance (p=0. 14).

In conclusion, the cemented group faired significantly better than the uncemented group. Our findings suggest the advantages of cement outweigh the disadvantages, and we support the use of cemented hemiarthroplasty for the displaced intracapsular femoral neck fracture in the elderly patient.

A total of 455 patients aged over 70 years with a displaced intracapsular fracture of the proximal femur was randomised to be treated either by hemiarthroplasty or internal fixation. The preoperative characteristics of the patients in both groups were similar.

Internal fixation has a shorter length of anaesthesia (36 minutes versus 57 minutes, p < 0.0001), lower operative blood loss (28 ml versus 177 ml, p < 0.0001) and lower transfusion requirements (0.04 units versus 0.39 units, p < 0.0001). In the internal fixation group 90 patients required 111 additional surgical procedures while only 15 additional operations on the hip were needed in 12 patients in the arthroplasty group. There was no statistically significant difference in mortality between the groups at one year (61/226 versus 63/229, p = 0.91), but there was a tendency for an improved survival in the older less mobile patients treated by internal fixation. For the survivors assessed at one, two and three years from injury there were no differences with regard to the outcome for pain and mobility. Limb shortening was more common after internal fixation (7.0 mm versus 3.6 mm, p = 0.004).

We recommend that displaced intracapsular fractures in the elderly should generally be treated by arthroplasty but that internal fixation may be appropriate for those who are very frail.