Tibial tubercle advancement osteotomy with bone allograft for patellofemoral arthritis: a retrospective cohort study of 50 knees.

PATIENTS AND METHODS: Forty consecutive patients (21 females and 19 males) in a single centre underwent 50 tibial tubercle advancement osteotomy procedures for patellofemoral arthritis between January 1993 and April 2007. Twenty knees with patellar maltracking also underwent medialisation of the tibial tubercle (6-12 mm) in addition to the standard 10-15 mm elevation. Femoral head bone allograft blocks were utilised in all cases, and all patients achieved bony union without further surgery. Forty-five knees had previously undergone arthroscopy, 18 with arthroscopic lateral releases. RESULTS: Ninety-four percentage of knees had sustained improvement in visual analogue pain scores (mean improvement of 37.4, P < 0.05) at a mean follow-up of 81 months (range 26-195 months), with 96% of patients still satisfied; and 92% of knees had sustained improvement in Shelbourne and Trumper anterior knee function scores (mean improvement of 39.8, P < 0.05). Overall clinical outcomes were rated excellent/good in 77%, fair in 35% and poor in 8% of knees. Two knees required arthroplasty surgery over the follow-up period (at 18 months and 8 years), and their anterior knee pain and function scores were not included in the analyses. Six knees (12%) suffered major complications: 1 temporary common peroneal neuropraxia; 2 intraoperative tibial metaphyseal fractures; and 3 tibial tuberosity fractures (at 8 days, 3 weeks and 3 months). Four knees (8%) suffered superficial wound infections, 31 knees had some numbness around the midline scar, 7 knees had scar pain lasting up to 12 months, and 22 knees (44%) experienced some discomfort relating to the metalwork, which was removed in all these cases. CONCLUSIONS: Tibial tubercle advancement osteotomy can be an effective treatment for anterior knee pain and for patients with arthroscopic evidence of patellar chondral damage. It can provide excellent/good long-term functional results in the majority of patients, with very high satisfaction levels and sustained improvement in pain symptoms. The use of femoral head bone allograft is both effective in obtaining bony union and by definition avoids the donor-site morbidity. Knees with patellar malalignment may also undergo individualised medialisation of the tibial tubercle such that the patella lies in the centre of the femoral trochlea, and may benefit from lateral trochleaplasty surgery in the presence of trochlear dysplasia. However, the major operative complication rate is high at 12%, and fracture of the tibial tubercle is associated with a poorer outcome. One can expect 10% of operated knees to have had some clinical deterioration in the patellofemoral joint by a mean follow-up of 93 months.

Bone mineral density in the femoral neck increases after hip resurfacing: a cohort with five-year follow-up.

Hip resurfacing is an effective treatment modality for arthritis of the hip in carefully selected patients; however, its use remains controversial due to its higher revision rates compared with conventional total hip replacement surgery. The most frequent reason for revision is femoral neck fracture, and preoperative bone mineral density is an important factor when considering the option of hip resurfacing. Whilst reduction in bone mineral density following total hip replacement is well documented, little is known about the long-term changes in femoral neck bone mineral density after hip resurfacing. We followed 15 patients (ten male and five female) who underwent unilateral hip resurfacing for osteoarthritis with standardised dual energy X-ray absorbiometry scans at two weeks, three months, one year, two years and five years postoperatively to determine changes in the femoral neck bone mineral density. Both males and females initially had decreases in bone mineral density at three months postoperatively, but had gradual mean increases to 119% of their initial measurements by five years. This study demonstrates that femoral neck bone mineral density increases after hip resurfacing and that this increase continues for at least five years.

Bilateral hip arthroplasty: is 1-week staging the optimum strategy?

Seventy-nine patients underwent bilateral hip arthroplasty staged either at 1 week (Group 1) or after greater intervals (as suggested by the patients, mean 44 weeks, range 16-88 weeks) (Group 2), over a five year period at one Institution. Sixty-eight patients (29 bilateral hip resurfacings and 39 total hip replacements) completed questionnaires regarding their post-operative recovery, complications and overall satisfaction with the staging of their surgery.There was no significant age or ASA grade difference between the patient groups. Complication rates in the two groups were similar and overall satisfaction rates were 84% in Group 1 (n = 32) and 89% in Group 2 (n = 36). Cumulative hospital lengths of stay were significantly longer in Group 1 patients (11.9 days vs 9.1 days)(p < 0.01); this was true for both hip resurfacing and total hip arthroplasty patients, however resurfacing patients stays were significantly shorter in both groups (p < 0.01). Postoperative pain resolved earlier in Group 1 patients at a mean of 20.9 weeks compared with a cumulative 28.9 weeks (15.8 and 13.1 weeks) for Group 2 patients (p = 0.03).The mean time to return to part-time work was 16.4 weeks for Group 1, and a cumulative 17.2 weeks (8.8 and 8.4 weeks) for Group 2. The time to return to full-time work was significantly shorter for Group 1 patients (21.0 weeks, compared with a cumulative 29.7 weeks for Group 2)(p < 0.05). The time to return to both full and part-time work was significantly shorter in total hip replacement patients with 1-week staging compared with delayed staging (22.0 vs 35.8 weeks (p = 0.02), and 13.8 vs 19.3 weeks (p = 0.03) respectively).Hip resurfacing patients in Group 2 had significantly shorter durations of postoperative pain and were able to return to part-time and full time work sooner than total hip arthroplasty patients. There was a general trend towards a faster recovery and resumption of normal activities following the second operation in Group 2 patients, compared with the first operation.Bilateral hip arthroplasty staged at a 1-week interval resulted in an earlier resolution of hip pain, and an earlier return to full-time work (particularly following total hip replacement surgery), with high levels of patient satisfaction and no increased risk in complications; however the hospital length of stay was significantly longer. The decision for the timing of staged bilateral surgery should be made in conjunction with the patient, making adjustments to accommodate their occupational needs and functional demands.

Differences in hip morphology between the sexes in patients undergoing hip resurfacing.

There is limited morphological data on the sex differences between the commonly used pelvic parameters. This study analysed the CT scans of 100 consecutive Caucasian patients, 61 males and 39 females, undergoing hip resurfacing arthroplasty surgery for hip osteoarthritis in one institution.There were no sex differences in femoral torsion/anteversion, femoral neck angle and acetabular inclination. Males had a mean femoral torsion/anteversion of 8 degrees (range -5 to 26 degrees), a mean femoral neck angle of 129 degrees (range 119 to 138 degrees) and a mean acetabular inclination of 55 degrees (range 40 to 86 degrees). Females had a mean femoral torsion/anteversion of 9 degrees (range -2 to 31 degrees), a mean femoral neck angle of 128 degrees (range 121 to 138) and a mean acetabular inclination of 57 degrees (range 44 to 80 degrees). Females had a significantly greater acetabular version of 23 degrees (range 10 to 53) compared with 18 degrees in males (range 7 to 46 degrees (p = 0.02) and males had a significantly greater femoral offset of 55 mm (range 42 to 68 mm) compared with 48 mm (range 37 to 57 mm) in females (p = 0.00). There were no significant differences between measurements taken from each patient's right and left hips.These findings may be useful for the future design and the implantation of hip arthroplasty components.

Granuloma debridement and the use of an injectable calcium phosphate bone cement in the treatment of osteolysis in an uncemented total knee replacement.

Polyethylene particulate debris-induced periprosthetic osteolysis is a known complication of knee arthroplasty surgery, and may result in the need for revision surgery. The management of these bony defects can be surgically challenging, and full revisions of well-fixed total knee components can lead to substantial bone loss. We present the case of a 71 year old man who developed knee pain and osteolysis around an uncemented total knee replacement. Due to significant medical comorbidies he was treated by percutaneous cyst granuloma debridement and grafting using an injectable calcium phosphate bone substitute. There were no wound complications, and the patient was allowed to fully weight-bear post-operatively. Histopathology and microbiology of the cyst material confirmed polyethylene granulomata without any evidence of infection. At 6 weeks post-operatively the patient's previous knee pain had resolved, he was able to comfortably fully weight-bear. Preoperative scores (Knee Society Score (KSS) 41, WOMAC score 46.2, and Oxford Knee Score 39) had all improved at the 12-month post-operative review KSS 76, WOMAC 81.7 and Oxford Knee score 21). This is a safe and effective technique with minimal morbidity and may be an appropriate treatment modality when more extensive revision surgery is not possible. The case is discussed with reference to the literature.

Changes in whole blood metal ion levels following resurfacing: serial measurements in a multi-centre study.

Seventy-seven patients implanted with unilateral resurfacing prosthesis were recruited from four centres. Serial whole blood samples were collected and ion levels were analysed. In most cases, the ion levels stabilized by 3 months. The 24 month median ion levels were 1.49ug/l for chromium and cobalt. In approximately 50% of patients the increase in chromium and cobalt level was less than 1ug/l. There were 6 patients with abnormally high metal ion levels. Of these 4 were significant outliers, had high ion levels that became apparent between 12 and 24 months after implantation, and had a high cup abduction angle. Not all patients with high cup abduction angles demonstrated high levels. There were differences in ion levels between the four centres that correlated with variation in acetabular component placement. Variability in ion levels was seen with the same prosthesis, underscoring the importance of surgical technique, longitudinal analysis, and multi-centre trials.

Bone biopsy of the parasymphyseal pubic bone region in athletes with chronic groin injury demonstrates new woven bone formation consistent with a diagnosis of pubic bone stress injury.

BACKGROUND: There is little scientific evidence available regarding the pathologic basis for chronic groin injury in athletes, a known difficult clinical problem. HYPOTHESIS: Histological analysis of the superior pubic ramus in athletes with diagnosed chronic groin injury may reveal the nature of the pathologic process. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Ten athletes with a diagnosis of chronic groin injury by clinical criteria (at least 6 weeks of pain) and magnetic resonance imaging criteria (unequivocal increase in T2 signal intensity) underwent bone biopsy of the superior pubic ramus. The biopsy site was located in the parasymphyseal region in the area of increased magnetic resonance image signal intensity. Histologic analysis of the specimens was then undertaken. RESULTS: Evidence of new woven bone was seen in all biopsy specimens. Signs of old bony injury were seen in 8 of the 10 specimens. There was no evidence of inflammation or osteonecrosis. CONCLUSION: Histologic analysis of bone biopsy specimens taken from the parasymphyseal pubic bone region with magnetic resonance imaging T2-weighted increased signal intensity of athletes diagnosed by clinical and magnetic resonance imaging criteria as having chronic groin injury demonstrates new woven bone formation. This is consistent with the athlete having a bone stress injury that may contribute significantly to athletic groin pain.

Hip joint range of motion restriction precedes athletic chronic groin injury.

Although a restricted hip range of motion has been previously associated with chronic groin injury the temporal course of this association remains unclear. Accordingly the purpose of this prospective cohort study was to report preliminary findings examining whether hip joint range of motion restriction is associated with subsequent onset of athletic chronic groin injury. End-range internal and external hip joint range of motion was determined in 29 elite Australian football players, without previous history of groin injury. The players were followed for two subsequent playing seasons for the development of chronic groin injury. Four athletes developed chronic groin injury defined as at least 6 weeks of groin pain and missing match playing time. In athletes that developed chronic groin injury a lower body weight (p=0.02) and reduced total hip joint range of motion (p=0.03) were found to be associated. This study suggests that hip stiffness is associated with later development of chronic groin injury and as such may be a risk factor for this condition. This work should be viewed as preliminary and caution is advised in applying the conclusion to clinical practice as the numbers in this study were small.

Single photon emission computed tomography in planning unicompartmental knee arthroplasty. A prospective study examining the association between scan findings and intraoperative assessment of osteoarthritis.

The aim of this study was to determine the relationship between preoperative single photon emission computed tomography (SPECT) scan findings and intraoperative assessments of knee osteoarthritis (OA) in patients undergoing tibiofemoral unicompartmental knee arthroplasty (UKA). Fifty knees in 46 patients undergoing UKA were investigated preoperatively with a SPECT scan to confirm unicompartmental disease. There were 38 men and 12 women in the cohort with an average age of 63 years (range 44-78). The SPECT scan uptake in each compartment of the knee was graded by a single radiologist and these findings were compared with intraoperative assessments of OA (size and grade of lesion), made by two experienced surgeons, blinded to the scan findings. Significant association was demonstrated between scan findings and OA in all compartments of the knee (p<0.05), and this was strongest in the medial compartment and weakest in the patellofemoral compartment and lateral tibial plateau. We conclude that SPECT scan is a useful imaging modality in the planning of medial tibiofemoral UKA to confirm unicompartmental disease. The lower degree of association between scan findings and OA encountered in the patellofemoral compartments and lateral tibial plateau indicates that greater vigilance should be exercised in the intraoperative assessment of these areas.

Debridement of wear granulomata in revision total hip arthroplasty: use of a chondrotome shaver blade.

Osteolysis is a common complication following uncemented total hip arthroplasty and is usually secondary to a biological reaction to polyethylene wear debris. The resultant periprosthestic bone resorption and granulomata is frequently not associated with implant loosening. In such circumstances, an option is to leave the well-fixed component, debride the granulomata, and exchange the polyethylene liner. We describe a simple method of accessing and debriding periprosthestic ranulomata using a chondrotome shaver blade.