Medical Care Use Among Patients with Monogenic Osteoporosis Due to Rare Variants in LRP5, PLS3, or WNT1

Pathogenic variants in the LRP5, PLS3, or WNT1 genes can significantly affect bone mineral density, causing monogenic osteoporosis. Much remains to be discovered about the phenotype and medical care needs of these patients. The purpose of this study was to examine the use of medical care among Dutch individuals identified between 2014 and 2021 with a pathogenic or suspicious rare variant in LRP5, PLS3, or WNT1. In addition, the aim was to compare their medical care utilization to both the overall Dutch population and the Dutch Osteogenesis Imperfecta (OI) population. The Amsterdam UMC Genome Database was used to match 92 patients with the Statistics Netherlands (CBS) cohort. Patients were categorized based on their harbored variants: LRP5, PLS3, or WNT1. Hospital admissions, outpatient visits, medication data, and diagnosis treatment combinations (DTCs) were compared between the variant groups and, when possible, to the total population and OI population. Compared to the total population, patients with an LRP5, PLS3, or WNT1 variant had 1.63 times more hospital admissions, 2.0 times more opened DTCs, and a greater proportion using medication. Compared to OI patients, they had 0.62 times fewer admissions. Dutch patients with an LRP5, PLS3, or WNT1 variant appear to require on average more medical care than the total population. As expected, they made higher use of care at the surgical and orthopedic departments. Additionally, they used more care at the audiological centers and the otorhinolaryngology (ENT) department, suggesting a higher risk of hearing-related problems.

Estimated cumulative radiation exposure in patients treated for adolescent idiopathic scoliosis

PURPOSE

Adolescent idiopoathic scoliosis (AIS) is a progressive spinal deformity, most often observed in female patients of pubescent age. The deformity's severity, its progression through time, its treatment and subsequent follow-up are assessed with routine radiological evaluation of the patient's full spine. This study aimed to determine the cumulative radiation exposure in average patients with AIS treated by brace or surgery throughout their treatment.

METHODS

The average number of imaging procedures and corresponding radiation doses were retrospectively obtained from the medical charts of AIS patients treated conservatively and/or surgically at our institution. The median radiation exposure of all imaging modalities was stated in effective dose (mSv). The estimated cumulative effective radiation dose of the each treatment group was determined by multiplication of the average number of imaging conducted, and the median effective radiation dose per imaging modality.

RESULTS

In total, 73 AIS patients were included (28 brace, 45 surgically). Patients treated with a brace were subjected to an average of 9.03 full spine radiographs, resulting in an estimated effective cumulative dose of 0.505 mSv over a median treatment period of 3.23 years. Patients treated surgically received an average of 14.29 full spine radiographs over a median treatment period of 2.76 years. The estimated effective cumulative dose amounted from 0.951 to 1.841 mSv, depending on the surgical technique.

CONCLUSION

The cumulative effective radiation doses rendered to AIS patients as part of their treatment and follow-up were relatively low. However, every exposure to ionising radiation for medical imaging purposes should be minimised.

Limited knee extension during gait after total knee arthroplasty is related to a low Oxford Knee Score

BACKGROUND

After total knee replacement (TKR) some patients report low self-perceived function, which is clinically measured using patient reported outcome measures (PROMs). However, PROMs, e.g. the Oxford Knee Score (OKS), inherently lack objective parameters of knee function. Biomechanical gait analysis is an objective and reliable measurement to quantitatively assess joint function. Therefore, the aim of this study was to explore the relationship between biomechanical gait parameters and the OKS.

METHODS

Gait analyses were recorded in 37 patients at least one year after primary TKR and in 24 healthy controls. Parameters from this analysis were calculated for hip, knee and ankle joint angles and joint moments in the sagittal and frontal plane including initial contact, early, late stance and swing. For the patients these parameters were expressed as its difference to control values at matched walking speed. Linear regression analyses were performed between the parameters from gait analysis and the OKS, with speed as covariate.

RESULTS

The difference in knee extension angle at initial contact and late stance between patients and controls was significantly related to the OKS. Per one degree knee extension difference increase, the OKS reduced with 1.0 to 1.6 points. Overall, patients extended their knee less than controls. Neither ankle and hip gait parameters, nor joint moments showed a relation with OKS.

CONCLUSIONS

All patients with a submaximal score on the OKS showed limited knee extension during gait, even without a mechanical constraint in knee extension. This could be related to motor control limitations in this patient group.

Patient-Reported Long-Term Outcomes After Free Vascularized Fibula Graft in Spinal Reconstruction: a 24-year Cohort

PURPOSE

The use of free vascularized fibula grafts (FVFG) in complex spinal deformity surgery intends to allow for life-long stability of the spine with good long-term clinical outcome. However, these long-term outcomes of this technique are still lacking. The objective of this study is to report the long-term postoperative outcomes and establish the long-term viability of this method for spinal reconstruction.

METHODS

A retrospective cohort study was conducted in all patients who underwent spinal reconstructive surgery utilizing a FVFG at a tertiary medical centre. Questionnaires taken from the participants were the Numeric Pain Rating Scale (NPRS), Oswestry Low Back Pain Disability (also known as Oswestry Disability Index (ODI)), Scoliosis Research Society 22r (SRS-22), the EQ-5D-5L and a self-assembled questionnaire regarding donor site comorbidities and patient satisfaction.

RESULTS

Over a period of 24 years (1995-2019), we used FVFG for spinal reconstruction in 31 patients. A total of 25 patients were included in this study, 8 patients were deceased at the time of this study, and sixteen patients responded to the questionnaires. Patient satisfaction was rated 6.8 out of 10, the average SRS-22r score was 3.6, EQ-5D-5L score was 0.725, and the ODI score showed a minimal disability (0-20%) postoperatively. Overall complication-free survival was 8.9 years. Nine patients underwent a re-operation in the spinal area; five for the removal of the spinal instrumentation.

CONCLUSION

Patients reported satisfied and good long-term outcomes following FVFG surgical procedure for complex spinal deformities. Therefore, considering the alternatives, this procedure provides a good long-term solution for complex spinal deformity surgery.

Accuracy assessment of pedicle screw insertion with patient specific 3D‑printed guides through superimpose CT-analysis in thoracolumbar spinal deformity surgery

PURPOSE

In order to avoid pedicle screw misplacement in posterior spinal deformity surgery, patient specific 3D‑printed guides can be used. An accuracy assessment of pedicle screw insertion can be obtained by superimposing CT-scan images from a preoperative plan over those of the postoperative result. The aim of this study is to report on the accuracy of drill guide assisted pedicle screw placement in thoracolumbar spinal deformity surgery by means of a superimpose CT-analysis.

METHODS

Concomitant with the clinical introduction of a new technique for drill guide assisted pedicle screw placement, the accuracy of pedicle screw insertion was analyzed in the first patients treated with this technique by using superimpose CT-analysis. Deviation from the planned ideal intrapedicular screw trajectory was classified according to the Gertzbein scale.

RESULTS

Superimpose CT-analysis of 99 pedicle screws in 5 patients was performed. The mean linear deviation was 0.92 mm, the mean angular deviation was 2.92° with respect to the preoperatively planned pedicle screw trajectories. According to the Gertzbein scale, 100% of screws were found to be positioned within the "safe zone".

CONCLUSION

The evaluated patient specific 3D-printed guide technology was demonstrated to constitute a safe and accurate tool for precise pedicle screw insertion in spinal deformity surgeries. Superimpose CT-analysis showed a 100% accuracy of pedicle screw placement without any violation of the pedicle wall or other relevant structures. We recommend a superimpose CT-analysis for the first consecutive patients when introducing new technologies into daily clinical practice, such as intraoperative imaging, navigation or robotics.

Gel-type autologous chondrocyte implantation for cartilage repair in patients with prior ACL reconstruction: A retrospective two year follow-up

PURPOSE

To describe the early patient-reported outcomes of articular cartilage repair in patients with pain due to grade III or IV articular cartilage defects after prior anterior cruciate ligament (ACL) reconstruction.

METHODS

Nineteen patients underwent a gel-type autologous chondrocyte implantation (GACI) procedure after ACL reconstruction. Median timeframe between ACL reconstruction and GACI procedure was 52 months (range 16 to 369). The average age at chondrocyte implantation was 35 (standard deviation (SD) eight) years and average cumulative articular cartilage defect size was nine (SD four) square centimeter. Outcome was assessed prior to the GACI procedure and two years after GACI using the International Knee Documentation Committee (IKDC) score and the Knee injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

Two year post-GACI scores showed a statistically significant improvement of IKDC (13, SD 22, p=.02) and KOOS quality of life (18, SD 27, p=.01) compared to the pre-GACI scores. The other KOOS domains did improve, but not statistically significant. Seven (37%) patients underwent reoperation after the GACI.

CONCLUSION

Patients with prior ACL reconstruction and suffering from ongoing pain associated with cartilage defects can benefit from cartilage repair with GACI.

Long-Term Creep Behavior of the Intervertebral Disk: Comparison between Bioreactor Data and Numerical Results

The loaded disk culture system is an intervertebral disk (IVD)-oriented bioreactor developed by the VU Medical Center (VUmc, Amsterdam, The Netherlands), which has the capacity of maintaining up to 12 IVDs in culture, for approximately 3 weeks after extraction. Using this system, eight goat IVDs were provided with the essential nutrients and submitted to compression tests without losing their biomechanical and physiological properties, for 22 days. Based on previous reports (Paul et al., 2012, 2013; Detiger et al., 2013), four of these IVDs were kept in physiological condition (control) and the other four were previously injected with chondroitinase ABC (CABC), in order to promote degenerative disk disease (DDD). The loading profile intercalated 16 h of activity loading with 8 h of loading recovery to express the standard circadian variations. The displacement behavior of these eight IVDs along the first 2 days of the experiment was numerically reproduced, using an IVD osmo-poro-hyper-viscoelastic and fiber-reinforced finite element (FE) model. The simulations were run on a custom FE solver (Castro et al., 2014). The analysis of the experimental results allowed concluding that the effect of the CABC injection was only significant in two of the four IVDs. The four control IVDs showed no signs of degeneration, as expected. In what concerns to the numerical simulations, the IVD FE model was able to reproduce the generic behavior of the two groups of goat IVDs (control and injected). However, some discrepancies were still noticed on the comparison between the injected IVDs and the numerical simulations, namely on the recovery periods. This may be justified by the complexity of the pathways for DDD, associated with the multiplicity of physiological responses to each direct or indirect stimulus. Nevertheless, one could conclude that ligaments, muscles, and IVD covering membranes could be added to the FE model, in order to improve its accuracy and properly describe the recovery periods.

Giant cell tumors of the sacrum--a nationwide study on midterm results in 26 patients after intralesional excision

PURPOSE

Evaluation of recurrences, complications and function at mid-term follow-up after curettage for sacral giant cell tumor (GCT).

METHODS

We retrospectively studied all 26 patients treated for sacral GCT in the Netherlands (from 1990 to 2010). Median follow-up was 98 (6-229) months. All patients underwent intralesional excision, 21 with local adjuvants, 5 radiotherapy, 3 IFN-α, 1 bisphosphonates. Functional outcome was assessed using Musculoskeletal Tumor Society (MSTS) score. Statistics were performed with Kaplan-Meier, Cox regression, log rank and Mann-Whitney U.

RESULTS

Recurrence rate was 14/26 after median 13 (3-139) months and was highest after isolated curettage (4/5). Soft tissue masses >10 cm increased recurrence risk (HR = 3.3, 95 % CI = 0.81-13, p = 0.09). Complications were reported in 12/26 patients. MSTS was superior in patients without complications (27 vs. 21; p = 0.024).

CONCLUSION

Recurrence rate for sacral GCT was highest after isolated curettage, indicating that (local) adjuvant treatment is desired to obtain immediate local control. Complications were common and impaired function.

Surface proteomic analysis of osteosarcoma identifies EPHA2 as receptor for targeted drug delivery

BACKGROUND

Osteosarcoma (OS) is the most common bone tumour in children and adolescents. Despite aggressive therapy regimens, treatment outcomes are unsatisfactory. Targeted delivery of drugs can provide higher effective doses at the site of the tumour, ultimately improving the efficacy of existing therapy. Identification of suitable receptors for drug targeting is an essential step in the design of targeted therapy for OS.

METHODS

We conducted a comparative analysis of the surface proteome of human OS cells and osteoblasts using cell surface biotinylation combined with nano-liquid chromatography - tandem mass spectrometry-based proteomics to identify surface proteins specifically upregulated on OS cells. This approach generated an extensive data set from which we selected a candidate to study for its suitability as receptor for targeted treatment delivery to OS. First, surface expression of the ephrin type-A receptor 2 (EPHA2) receptor was confirmed using FACS analysis. Ephrin type-A receptor 2 expression in human tumour tissue was tested using immunohistochemistry. Receptor targeting and internalisation studies were conducted to assess intracellular uptake of targeted modalities via EPHA2. Finally, tissue micro arrays containing cores of human OS tissue were stained using immunohistochemistry and EPHA2 staining was correlated to clinical outcome measures.

RESULTS

Using mass spectrometry, a total of 2841 proteins were identified of which 156 were surface proteins significantly upregulated on OS cells compared with human primary osteoblasts. Ephrin type-A receptor 2 was highly upregulated and the most abundant surface protein on OS cells. In addition, EPHA2 was expressed in a vast majority of human OS samples. Ephrin type-A receptor 2 effectively mediates internalisation of targeted adenoviral vectors into OS cells. Patients with EPHA2-positive tumours showed a trend toward inferior overall survival.

CONCLUSION

The results presented here suggest that the EPHA2 receptor can be considered an attractive candidate receptor for targeted delivery of therapeutics to OS.

Slipped capital femoral epiphysis and its association with endocrine, metabolic and chronic diseases: a systematic review of the literature

PURPOSE

Puberty, obesity, endocrine and chronic systemic diseases are known to be associated with slipped capital femoral epiphysis (SCFE). The mechanical insufficiency of the physis in SCFE is thought to be the result of an abnormal weakening of the physis. However, the mechanism at the cellular level has not been unravelled up to now.

METHODS

To understand the pathophysiology of endocrine and metabolic factors acting on the physis, we performed a systematic review focussing on published studies reporting on hormonal, morphological and cellular abnormalities of the physis in children with SCFE. In addition, we looked for studies of the effects of endocrinopathies on the human physis which can lead to cause SCFE and focussed in detail on hormonal signalling, hormone receptor expression and extracellular matrix (ECM) composition of the physis. We searched in the PubMed, EMBASE.com and The Cochrane Library (via Wiley) databases from inception to 11th September 2012. The search generated a total of 689 references: 382 in PubMed, 232 in EMBASE.com and 75 in The Cochrane Library. After removing duplicate papers, 525 papers remained. Of these, 119 were selected based on titles and abstracts. After excluding 63 papers not related to the human physis, 56 papers were included in this review.

RESULTS

Activation of the gonadal axis and the subsequent augmentation of the activity of the growth hormone-insulin-like growth factor 1 (GH-IGF-1) axis are important for the pubertal growth spurt, as well as for cessation of the physis at the end of puberty. The effects of leptin, thyroid hormone and corticosteroids on linear growth and on the physis are also discussed. Children with chronic diseases suffer from inflammation, acidosis and malnutrition. These consequences of chronic diseases affect the GH-IGF-1 axis, thereby, increasing the risk of the development of SCFE. The risk of SCFE and avascular necrosis in children with chronic renal insufficiency, growth hormone treatment and renal osteodystrophy remains equivocal.

CONCLUSIONS

SCFE is most likely the result of a multi-factorial event during adolescence when height and weight increase dramatically and the delicate balance between the various hormonal equilibria can be disturbed. Up to now, there are no screening or diagnostic tests available to predict patients at risk.

Incidence and gender differences of slipped capital femoral epiphysis in the Netherlands from 1998-2010 combined with a review of the literature on the epidemiology of SCFE

PURPOSE

The incidence of slipped capital femoral epiphysis (SCFE) among children living in the Netherlands has never been published.

METHODS

The national hospitalization registration system of the Netherlands was searched for the incidence of surgical procedures for SCFE in the Netherlands among different pediatric age groups between 1998 and 2010. International Classification of Diseases, 9th Revision codes were used.

RESULTS AND CONCLUSION

The incidence of surgical procedures for SCFE during the last decade was 11.6 per 100,000 children aged 5 to 19 years. No statistical difference in the incidence of SCFE was found between boys and girls, although the incidence of SCFE did significantly increase in girls during the study period. Based on our analysis, the Netherlands appears to be the first country in which no difference in the incidence of SCFE among boys and girls has been reported. However, during the study period there has been a concomitant increase in the number of girls with SCFE.

Molecular alterations as target for therapy in metastatic osteosarcoma: a review of literature

Treating metastatic osteosarcoma (OS) remains a challenge in oncology. Current treatment strategies target the primary tumour rather than metastases and have a limited efficacy in the treatment of metastatic disease. Metastatic cells have specific features that render them less sensitive to therapy and targeting these features might enhance the efficacy of current treatment. A detailed study of the biological characteristics and behaviour of metastatic OS cells may provide a rational basis for innovative treatment strategies. The aim of this review is to give an overview of the biological changes in metastatic OS cells and the preclinical and clinical efforts targeting the different steps in OS metastases and how these contribute to designing a metastasis directed treatment for OS.

Posterior lumbar interbody fusion using non resorbable poly-ether-ether-ketone versus resorbable poly-L-lactide-co-D,L-lactide fusion devices. Clinical outcome at a minimum of 2-year follow-up

Previous papers on resorbable poly-L-lactide-co-D,L-lactide (PLDLLA) cages in spinal fusion have failed to report adequately on patient-centred clinical outcome measures. Also comparison of PLDLLA cage with a traditionally applicable counterpart has not been previously reported. This is the first randomized prospective study that assesses clinical outcome of PLDLLA cage compared with a poly-ether-ether-ketone (PEEK) implant. Twenty-six patients were randomly assigned to undergo instrumented posterior lumbar interbody fusion (PLIF) whereby either a PEEK cage or a PLDLLA cage was implanted. Clinical outcome based on visual analogue scale scores for leg pain and back pain, as well as Oswestry Disability Index (ODI) and SF-36 questionnaires were documented and analysed. When compared with preoperative values, all clinical parameters have significantly improved in the PEEK group at 2 years after surgery with the exception of SF-36 general health, SF-36 mental health and SF-36 role emotional scores. No clinical parameter showed significant improvement at 2 years after surgery compared with preoperative values in the PLDLLA patient group. Only six patients (50%) in the PLDLLA group showed improvement in the VAS scores for leg and back pain as well as the ODI, as opposed to 10 patients (71%) in the PEEK group. One-third of the patients in the PLDLLA group actually reported worsening of their pain scores and ODI. Three cases of mild to moderate osteolysis were seen in the PLDLLA group. Following up on our preliminary report, these 2-year results confirm the superiority of the PEEK implant to the resorbable PLDLLA implant in aiding spinal fusion and alleviating symptoms following PLIF in patients with degenerative spondylolisthesis associated with either canal stenosis or foramen stenosis or both and emanating from a single lumbar segment.

Prolonged treatment with the Pavlik harness in infants with developmental dysplasia of the hip

We prospectively studied the benefits and risks of prolonged treatment with the Pavlik harness in infants with idiopathic developmental dysplasia of the hip. Bracing was continued as long as abduction improved. It was started at a mean age of four months (1 to 6.9). Outcome measures were the number of successful reductions, the time to reduction, the acetabular index and evidence of avascular necrosis at follow-up at one year. In 50 infants with 62 subluxated and dislocated hips (42 Graf type III and 20 type IV), 37 were reduced successfully with a mean time to reduction of 13.4 weeks (sd 6.8). Bracing was successful in 31 type-III (73.8%) and in only six type-IV hips (20%, p = 0.002). Avascular necrosis was seen in ten hips. Prolonged treatment with the Pavlik harness for developmental dysplasia of the hip over the age of one month can be beneficial in type-III hips, but it is unclear as to whether this is the optimal treatment, since it may postpone the need for closed or open reduction to a more unfavourable age. The use of the Pavlik harness in type-IV hips in this age group is questionable, but if used, prolonged bracing is not advised.

Resorbability of rigid beta-tricalcium phosphate wedges in open-wedge high tibial osteotomy: a retrospective radiological study

The open-wedge high tibial osteotomy (OWHTO) is a well accepted treatment modality for patients with osteoarthritis of the medial compartment associated with genu varum. To fill in the osteotomy gap 30% macroporosity rigid beta-tricalcium phosphate (beta-TCP) is frequently used as a stable resorbable bone substitute. However, the resorbability of these beta-TCP wedges is not known. The aim of this study was to investigate this. Twenty-one OWHTO procedures in seventeen patients were performed with the use of 30% macroporosity rigid beta-TCP wedges. The osteotomies were fixed using an angle-stable locking plate. Conventional AP and lateral radiographs were examined in order to assess the resorbability of the 30% macroporosity rigid beta-TCP wedges as a function of time. A radiological classification system consisting of five phases was used to monitor the resorption of the 30% macroporosity rigid beta-TCP wedges. The mean duration of follow-up was 62 months (+/-23 range of 28-99). In all 21 cases, remnants of the 30% macroporosity rigid beta-TCP wedges were still present at maximum follow-up. Although the boundaries between 30% macroporosity rigid beta-TCP wedges and bone remained slightly visible, all osteotomies were completely consolidated and full osseointegration took place. In 16 out of 21 knees the fixation system was removed after a mean duration of 32 months (+/-19 range of 6-62). In six out of 21 knees a conversion to a knee arthroplasty was performed after a mean duration of 56 months (+/-18 range of 37-82). The OWHTO did not interfere with the placement of knee prostheses. Complete resorption of 30% macroporosity rigid beta-TCP wedges did not take place up to 8 years after operation.

Basilar impression in osteogenesis imperfecta: can it be treated with halo traction and posterior fusion?

Basilar impression (BI) and hydrocephalus complicating osteogenesis imperfecta (OI) is usually treated by anterior transoral decompression and posterior fixation. Nevertheless, it may be questioned if posterior fusion following axial halo traction is adequate in patients with symptomatic BI complicating OI. We report on a case with progressive symptomatic hydrocephalus and BI complicating OI that was successfully treated by halo traction followed by posterior occipitocervical fusion. However, after a symptom free interval of 2 years the patient suffered from recurrence of symptomatic hydrocephalus needing additional ventriculoperitoneal (VP) shunt placement. In conclusion, posterior fusion without additional VP shunt placement may not be effective in the long term for ameliorating symptoms and signs and halting progressive hydrocephalus in BI complicating OI.

ASAS/EULAR recommendations for the management of ankylosing spondylitis

OBJECTIVE

To develop evidence based recommendations for the management of ankylosing spondylitis (AS) as a combined effort of the 'ASsessment in AS' international working group and the European League Against Rheumatism.

METHODS

Each of the 22 participants was asked to contribute up to 15 propositions describing key clinical aspects of AS management. A Delphi process was used to select 10 final propositions. A systematic literature search was then performed to obtain scientific evidence for each proposition. Outcome data for efficacy, adverse effects, and cost effectiveness were abstracted. The effect size, relative risk, number needed to treat, and incremental cost effectiveness ratio were calculated. On the basis of the search results, 10 major recommendations for the management of AS were constructed. The strength of recommendation was assessed based on the strength of the literature evidence, risk-benefit trade-off, and clinical expertise.

RESULTS

The final recommendations considered the use of non-steroidal anti-inflammatory drugs (NSAIDs) (conventional NSAIDs, coxibs, and co-prescription of gastroprotective agents), disease modifying antirheumatic drugs, treatments with biological agents, simple analgesics, local and systemic steroids, non-pharmacological treatment (including education, exercise, and physiotherapy), and surgical interventions. Three general recommendations were also included. Research evidence (categories I-IV) supported 11 interventions in the treatment of AS. Strength of recommendation varied, depending on the category of evidence and expert opinion.

CONCLUSION

Ten key recommendations for the treatment of AS were developed and assessed using a combination of research based evidence and expert consensus. Regular updating will be carried out to keep abreast of new developments in the management of AS.

Histopathology of retrieved allografts of the femoral head

From November 1994 to March 1997, we harvested 137 grafts of the femoral head from 125 patients for donation during total hip arthroplasty according to the guidelines of the American Associations of Tissue Banks (AATB) and the European Association of Musculo-Skeletal transplantation (EAMST). In addition to the standards recommended by these authorities, we performed histopathological examination of a core biopsy of the retrieved bone allograft and of the synovium.

Of the 137 allografts, 48 (35.0%) fulfilled all criteria and were free for donation; 31 (22.6%) were not regarded as suitable for transplantation because the serological retests at six months were not yet complete and 58 (42.3%) were discarded because of incomplete data. Of those discarded, five showed abnormal histopathological findings; three were highly suspicious of low-grade B-cell lymphoma, one of monoclonal plasmacytosis and the other of non-specific inflammation of bone marrow. However, according to the standards of the AATB or EAMST they all met the criteria and were eligible for transplantation.

Our findings indicate that the incidence of abnormal histopathology in these retrieved allografts was 3.6%. Since it is essential to confirm the quality of donor bones in bone banking, we advise that histopathological screening of donor bone should be performed to exclude abnormal allografts.

Histopathology of retrieved allografts of the femoral head

From November 1994 to March 1997, we harvested 137 grafts of the femoral head from 125 patients for donation during total hip arthroplasty according to the guidelines of the American Associations of Tissue Banks (AATB) and the European Association of Musculo-Skeletal transplantation (EAMST). In addition to the standards recommended by these authorities, we performed histopathological examination of a core biopsy of the retrieved bone allograft and of the synovium. Of the 137 allografts, 48 (35.0%) fulfilled all criteria and were free for donation; 31 (22.6%) were not regarded as suitable for transplantation because the serological retests at six months were not yet complete and 58 (42.3%) were discarded because of incomplete data. Of those discarded, five showed abnormal histopathological findings; three were highly suspicious of low-grade B-cell lymphoma, one of monoclonal plasmacytosis and the other of non-specific inflammation of bone marrow. However, according to the standards of the AATB or EAMST they all met the criteria and were eligible for transplantation. Our findings indicate that the incidence of abnormal histopathology in these retrieved allografts was 3.6%. Since it is essential to confirm the quality of donor bones in bone banking, we advise that histopathological screening of donor bone should be performed to exclude abnormal allografts.

Polysegmental lumbar posterior wedge osteotomies for correction of kyphosis in ankylosing spondylitis

Between 1984 and 1993 we treated 21 consecutive patients who had progressive thoracic kyphosis due to ankylosing spondylitis by polysegmental posterior lumbar wedge osteotomies. In 19 patients we used the Universal Spinal Instrumentation System and in the last 2 patients the H-frame. The average correction in 20 of 21 patients at follow-up was 25.6 degrees (range 0 degrees-52 degrees), with a mean segmental correction of 9.5 degrees and a mean loss of correction after operation of 10.7 degrees (range 0 degrees-36 degrees). There were no fatal complications, but in one patient no correction could be obtained during surgery and another patient was reoperated due to lack of correction. Breaking out of screws through the pedicle during compressive correction was seen in seven patients. Implant failure, such as breakage of the threaded rods and/or loosening of the junction between the pedicle screw and the rod, occurred in 9 out of 21 patients. Two patients required reoperation at long-term follow-up. Five out of seven deep wound infections required removal of the implant. Polysegmental lumbar wedge osteotomies for correction of progressive thoracic kyphosis in ankylosing spondylitis is only recommended in patients at a mild stage of the disease with mobile discs and in combination with strong instrumentation.

Correction of a dystrophic cervicothoracic spine deformity in Recklinghausen's disease

A case is presented of a 14-year-old boy with neurofibromatosis who had a 92 degrees dystrophic kyphosis (as measured on radiographs between C3 and C7) of the cervical spine. He was treated successfully by posterior stabilization and anterior fusion using a free vascularized fibula graft. This method appears to be an attractive alternative to an avascular fibula graft and avoids the risk of graft resorption (creeping substitution), weakening (fracture), or nonunion during the process of bony consolidation. It provides a stable and longstanding anterior strut, essential in the management of high grades of kyphosis. At 1-year followup the patient has no symptoms, is fully mobile, and shows radiographically complete incorporation of the graft with no loss of correction.

Treatment of frozen shoulder by distension and manipulation under local anaesthesia

We report the results of hydraulic distension of the glenohumeral joint with manipulation using local anaesthesia and radiographic control in 24 frozen shoulders in 22 patients. In a prospective study, the pre- and postoperative range of movement in 3 planes was measured by an electronic digital inclinometer. At 3 months, the range compared with the unaffected shoulder was abduction 93%, glenohumeral abduction 84%, forward flexion 94%, backward extension 96%, internal rotation 75% and external rotation 73%. The procedure was repeated once in 3 patients. One also had a manipulation under general anaesthesia and was classed as a failure. The subjective outcome was good in all the other patients. This investigation shows that the technique is safe, reliable and effective treatment for frozen shoulder.

Closing-wedge posterior osteotomy for ankylosing spondylitis. Partial corporectomy and transpedicular fixation in 22 cases

From 1990 to 1993 we treated 22 consecutive patients who had progressive spinal kyphosis due to ankylosing spondylitis by a closing-wedge posterior vertebral osteotomy with partial corporectomy of L4 and transpedicular fixation. The average correction was 32 degrees (24 to 52) with a mean loss of correction after operation of 2.7 degrees (0 to 13). The average operating time was 185 minutes (135 to 240) and blood loss was 2500 ml (1200 to 5000). The osteotomy corrected all patients sufficiently to allow them to see ahead and their posture was improved. There were no fatal complications, but in two cases there was failure of the instrumentation and one patient needed reoperation for nerve compression. Two deep wound infections required removal of the implant and six patients had superficial skin infections under the plaster. The use of a circoelectric bed and intermittent prone lying eliminated this problem.

Effects of immobilization and continuous passive motion on postoperative muscle atrophy in mature rabbits

The effects of continuous passive motion and cast immobilization on muscle atrophy were compared 3 weeks after bilateral arthrotomies on 10 mature New Zealand rabbits. The gastrocnemius, rectus femoris and tibialis anterior muscles were excised and weighed, and the dry weights of the gastrocnemius were also determined. The protein concentration and cross-sectional areas of types I and II muscle fibres in the rectus femoris and tibialis anterior muscles were measured. Compared with the results in rabbits treated by cast immobilization, continuous passive motion significantly (p less than 0.05) reduced muscle atrophy as determined from the wet and dry weights of the gastrocnemius muscles, the protein content in the tibialis anterior muscles and the cross-sectional areas of the type II fibres in the rectus femoris muscles.

A comparison of the effects of immobilization and continuous passive motion on surgical wound healing in mature rabbits

The purpose of this investigation was to compare the effects of continuous passive motion (CPM) and cast immobilization on postoperative wound healing. Medical parapatellar skin incisions and arthrotomies were performed on both knees of 10 mature New Zealand rabbits. After closure of the incisions, one knee was immobilized in a cast while the other was treated by continuous passive motion for 3 weeks. Six standardized skin specimens (2 mm wide) from each wound were tested to failure and one specimen was examined histologically. With respect to the breaking force, tensile strength, strain at failure, stiffness, and toughness, the wounds in the continuous-passive-motion group were significantly stronger, stiffer, and tougher than those in the cast group. Histologically, the structural organization of the collagen fibers was also superior in the scars treated with continuous passive motion. The results of the present investigation indicate that compared to immobilization, continuous passive motion enhances postoperative wound healing in rabbits.