The principle function of the “short external rotator” muscle group is primarily as an abductor and extensor of the flexed hip and is better referred to as the “Quadriceps Coxa” (QC). The QC has a profound influenced on weight bearing rising and propulsive motions. The SPAIRE technique preserves Obturator Internus (OI) and Piriformis (P) resulting in improved stability of the hip and potentially improved recovery and function in patients undergoing hip arthroplasty. Short term outcomes of the first 42 consecutive SPAIRE cases are compared with 86 consecutive cases using the traditional posterior approach that immediately preceded introduction of the technique. The purpose was to document the learning curve and confirm the safety of introducing SPAIRE into routine clinical practice. The two groups were comparable and there was no statistically significant difference in length of stay, blood loss, intra-or post-operative complications nor radiological measurements relating to the femoral or acetabular components. Statistically significant differences were found for component usage (more uncemented acetabula for SPAIRE), length of operation (8 mins longer with SPAIRE); patient satisfaction was higher at 6 weeks and measured leg length discrepancy less in the SPAIRE group. SPAIRE has been used routinely for all routine arthroplasties for over two years. RCTs are ongoing to document the effect of SPAIRE on recovery, long term function and activity level. If the potential benefits are confirmed SPAIRE may become the default technique for hip arthroplasty operations through a posterior approach for elective and hip fracture cases

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.

The aim of this review is to evaluate the current available literature evidencing on peri-articular hip endoscopy (the third compartment). A comprehensive approach has been set on reports dealing with endoscopic surgery for recalcitrant trochanteric bursitis, snapping hip (or coxa-saltans; external and internal), gluteus medius and minimus tears and endoscopy (or arthroscopy) after total hip arthroplasty. This information can be used to trigger further research, innovation and education in extra-articular hip endoscopy.

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.

The SPAIRE technique (Saving Piriformis And Internus, Repair Externus) was first described in 2016 and an approach to the hip in the interval between the inferior gemellus and quadratus femoris can be used for both hemi- and total hip arthroplasty. The HemiSPAIRE technique in hip hemiarthroplasty for displaced intracapsular fractures has been compared with the standard lateral approach (advocated by NICE) in a pragmatic, superiority, multicentre, randomised controlled trial into postoperative mobility and function. This NIHR funded study was recruited between November 2019 and April 2022 and the results are reported in this presentation. The author has used the SPAIRE technique in 1026 routine primary total hip replacements since February 2016. The technique is described along with results from NJR data. SPAIRE is most challenging in patients with small anatomy, reduced offset, with an external rotation deformity. Particularly in these, but in all cases, MAKO robotic assistance facilitates accurate implantation of prostheses and precise recreation of biomechanics. The MAKO robot has been used in all cases since 2018 and SPAIRE/MAKO is now the standard of care in the author's practice. To evaluate whether robotic-assisted tendon-sparing posterior approaches (piriformis sparing and SPAIRE), improve patient outcomes in total hip arthroplasty compared with a robotic-assisted standard posterior approach, the NIHR Efficacy and Mechanism Evaluation Programme has recently funded the HIPSTER trial (HIP Surgical Techniques to Enhance Rehabilitation). This is a single-centre, double-blinded, parallel three-arm, randomised, controlled, superiority trial; recruitment is in progress. The greatest value of robotic assistance may be when it is used in combination with tendon-sparing surgery. Data is being gathered to evaluate whether the SPAIRE/MAKO technique confers benefits with regard the speed of post-op mobilisation as well as accelerated return to unrestricted function

The SPAIRE technique (Spare Piriformis And Internus, Repair Externus) involves a muscle sparing mini-posterior approach to the hip. Evidence will be prevented that the principle function of the “short external rotator” muscle group is primarily as an abductor and extensor of the flexed hip and has a profound influenced on weight bearing rising and propulsive motions; also that details of the insertions of the piriformis tendon and conjoint insertion of obturator internus and the gemelli (the Quadriceps Coxa) have previously been poorly appreciated. We have developed a surgical technique (SPAIRE) during which the only tendon released, and subsequently repaired, is obturator externus. The author has carried out the SPAIRE technique for all routine hip arthroplasties for the last 18 months. This cohort has been compared with a matched control group for a comprehensive array of outcome measures. Results show no disadvantage of using the technique. On-table stability is so impressive that when the SPAIRE technique has been used no postoperative restrictions whatsoever are placed on the patient who is immediately encouraged to exercise the hip through a full excursion of movement. Fewer tendons are damaged using the SPAIRE technique than any other approach to the hip including Direct Anterior and Direct Superior approaches. Randomised prospective studies are on-going using objective measurements of Gait and muscle power as well as functional and patient reported outcomes to prove benefit of the SPAIRE technique. For hemiarthroplasty cases a separate RCT is being undertaken comparing the SPAIRE technique with a direct lateral approach. It is believed that this technique may become the default technique for hemi- and total- hip arthroplasty through a posterior approach and for all hip fracture arthroplasty cases

Aims

The primary objective of this study was to develop a validated classification system for assessing iatrogenic bone trauma and soft-tissue injury during total hip arthroplasty (THA). The secondary objective was to compare macroscopic bone trauma and soft-tissues injury in conventional THA (CO THA) versus robotic arm-assisted THA (RO THA) using this classification system.

Aims

Although the short stem concept in hip arthroplasty procedure shows acceptable clinical performance, we sometimes get unexplainable radiological findings. The aim of this retrospective study was to evaluate changes of radiological findings up to three years postoperatively, and to assess any potential contributing factors on such radiological change in a Japanese population.

Aims

The gluteus minimus (GMin) and gluteus medius (GMed) have unique structural and functional segments that may be affected to varying degrees, by end-stage osteoarthritis (OA) and normal ageing. We used data from patients with end-stage OA and matched healthy controls to 1) quantify the atrophy of the GMin and GMed in the two groups and 2) describe the distinct patterns of the fatty infiltration in the different segments of the GMin and GMed in the two groups.

Aims

We wished to quantify the extent of soft-tissue damage sustained during minimally invasive total hip arthroplasty through the direct anterior (DA) and direct superior (DS) approaches.

The inferior gluteal artery is described in standard anatomy textbooks as contributing to the blood supply of the hip through an anastomosis with the medial femoral circumflex artery. The site(s) of the anastomosis has not been described previously. We undertook an injection study to define the anastomotic connections between these two arteries and to determine whether the inferior gluteal artery could supply the lateral epiphyseal arteries alone. From eight fresh-frozen cadaver pelvic specimens we were able to inject the vessels in 14 hips with latex moulding compound through either the medial femoral circumflex artery or the inferior gluteal artery. Injected vessels around the hip were then carefully exposed and documented photographically.

In seven of the eight specimens a clear anastomosis was shown between the two arteries adjacent to the tendon of obturator externus. The terminal vessel arising from this anastomosis was noted to pass directly beneath the posterior capsule of the hip before ascending the superior aspect of the femoral neck and terminating in the lateral epiphyseal vessels. At no point was the terminal vessel found between the capsule and the conjoined tendon. The medial femoral circumflex artery receives a direct supply from the inferior gluteal artery immediately before passing beneath the capsule of the hip.

Detailed knowledge of this anatomy may help to explain the development of avascular necrosis after hip trauma, as well as to allow additional safe surgical exposure of the femoral neck and head.

When the Bernese periacetabular osteotomy is performed through an anterior approach, the ischial and retroacetabular osteotomies and manual fracture of the incompletely osteotomised ischium are conducted with an incomplete view resulting in increased risk and morbidity. We have assessed the dual anteroposterior approach which appears to address this deficiency.

We compared the results of the Bernese periacetabular osteotomy performed in 11 patients (13 osteotomies) through a single anterior approach with those in 12 patients (13 osteotomies) in whom the procedure was carried out through a dual anteroposterior approach. The estimated blood loss, the length of anaesthesia, duration of surgery and radiological parameters were measured.

The mean operative time and length of anaesthesia were not significantly different in the two groups (p = 0.781 and p = 0.698, respectively). The radiological parameters improved to a similar extent in both groups after the operation but there was significantly less blood loss in the dual osteotomy group (p = 0.034).

The dual anteroposterior approach provides a direct view of the retroacetabular and ischial parts of the osteotomy, within a reasonable operating time and with minimal blood loss and gives a satisfactory outcome.