No difference in clinical outcome at 2-year follow-up in patients with type III and V acromioclavicular joint dislocation treated with hook plate or physiotherapy: a randomized controlled trial

BACKGROUND

The need for operative treatment of acute acromioclavicular (AC) joint dislocation is unclear. The purpose of this randomized controlled trial was to compare the outcomes after operative treatment with a hook plate with the outcomes after nonoperative treatment of acute Rockwood type III and type V AC joint dislocations separately.

METHODS

The inclusion criteria were patients aged 18-65 years with an acute type III or type V AC joint dislocation with the availability to start treatment within 3 weeks after trauma. All patients received the same standardized outpatient rehabilitation protocol and were followed up for 24 months. Assessments were based on radiographs, clinical examination findings, and questionnaires. The primary outcome was the Constant score (CS). The secondary outcomes were as follows: Subjective Shoulder Value (SSV), QuickDASH score (abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire), shoulder pain at rest and during movement rated using a visual analog scale, EQ-5D (European Quality of Life 5 Dimensions) score, patient satisfaction, cosmesis, complications, and adverse events. The 4 groups were compared using 1-way analysis of variance and intention to treat.

RESULTS

The included patients (N = 124) (mean age, 40 years [range, 18-64 years]; 91% male patients) were randomized, stratified by type, to nonoperative treatment (type III, n = 33; type V, n = 30) or operative treatment with a hook plate (type III, n = 30; type V, n = 31) at a single center. Three patients randomized to physiotherapy dropped out before any follow-up measures, leaving 121 patients in the study. Complete clinical follow-up data were obtained from 118 patients at 24 months. At 3 months, patients in both nonoperatively treated groups had a significantly better mean CS, SSV, and QuickDASH score and had less pain at rest and during movement compared with patients treated operatively. At 6, 12, and 24 months, there were no significant differences in the CS, SSV, QuickDASH score, pain, or EQ-5D score between the groups regardless of intervention. At 24 months, the mean CS was 88 for nonoperatively treated type III patients vs. 91 for operatively treated type III patients and was 90 vs. 91 for type V patients (P = .477). At final follow-up, patients had regained 97% of the mean CS comparing the uninjured and injured shoulders and 86% of the patients rated the result as excellent or good. Eleven patients assigned to nonoperative treatment (18%, 6 type III and 5 type V) underwent surgery within 19 months.

CONCLUSIONS

Both the nonoperative and operative treatment groups had very good restoration of shoulder function and patient satisfaction at 24 months, and operative treatment did not lead to better outcomes compared with nonoperative treatment. In conclusion, our study does not support surgery with a hook plate in patients with acute Rockwood type III or type V AC joint dislocations.

SABER-Bupivacaine Reduces Postoperative Pain and Opioid Consumption After Arthroscopic Subacromial Decompression: A Randomized, Placebo-Controlled Trial

INTRODUCTION

Shoulder arthroscopy can result in substantial postoperative pain. Sucrose acetate isobutyrate extended-release bupivacaine (SABER-Bupivacaine; trade name Posimir) is a novel depot formulation of bupivacaine designed to provide analgesia at the surgical site for up to 72 hours. The objective of this study was to evaluate the effect of SABER-Bupivacaine on pain and opioid consumption after arthroscopic subacromial decompression and to assess short-term and long-term safety.

METHODS

In this double-blind, placebo-controlled trial, 78 subjects were randomized in a 2:1 ratio to SABER-Bupivacaine 5 mL or SABER-placebo 5 mL injected into the subacromial space just before skin closure. Twenty-nine additional subjects were randomized on an exploratory basis to bupivacaine hydrochloride 20 mL, also injected subacromially. Subjects rated pain intensity on a 0 to 10 scale over the first 3 postoperative days and received intravenous or oral morphine for breakthrough pain. The coprimary efficacy end points were pain intensity on 90° shoulder flexion and cumulative morphine intake from 0 to 72 hours after surgery. The time to first use of opioid rescue analgesia was a secondary end point.

RESULTS

The mean (SD) pain intensity was 5.16 (1.94) for SABER-Bupivacaine and 6.43 (1.77) for placebo (P = 0.012). The median consumption of intravenous morphine equivalents was 4.0 mg for SABER-Bupivacaine and 12.0 mg for placebo (P = 0.010). The median time to first use of morphine rescue was 12.4 hours for SABER-Bupivacaine and 1.2 hours for placebo (P = 0.014). The corresponding values for bupivacaine hydrochloride were 5.16 (2.38), 8.0 mg, and 1.4 hours. The incidence and severity of treatment-emergent adverse events were similar for all treatment groups, and no functional or radiographic differences were noted at the 6-month follow-up.

DISCUSSION

Compared with placebo, SABER-Bupivacaine reduced pain and opioid analgesic consumption over 72 hours after arthroscopic subacromial decompression and prolonged the time to first use of opioid rescue analgesia. No safety signals were noted during the immediate postoperative period or at 6-month follow-up.

Intramedullary nailing of dislocated midshaft clavicle fractures with the Rockwood Clavicle Pin, a retrospective study

This retrospective study evaluated the outcome after intramedullary nailing with the Rockwood Clavicle Pin (RCP) for acute displaced middle third clavicle fractures in adults. Of 84 included patients treated for this fracture 2003-2009, 66 (79%) were evaluated. Of these, 52 (79%) were re-examined, including fluoroscopy, while 14 patients (21%) were evaluated by mailed questionnaire. Primary outcome was Constant score (CS), secondary outcomes included : Subjective Shoulder Value (SSV), healing rate at follow up, complications, and cosmetic appearance. Patients were re-evaluated with a mean follow-up of 39 months (range 13-96). Mean CS at follow up was 90 (range 55-100) and mean shoulder function measured with the SSV was 93 (range 36-100). Three (6%) of the re-examined patients had a non-union at follow up. Twelve (18%) had wound problems, with exposure of the lateral part of the pin in five patients (8%). There were no deep infections but seven patients (11%) were treated for superficial wound infections. Breakage of the implant occurred in one case (2%). Treatment of displaced midshaft clavicle fractures with the RCP results in good clinical outcome and a high patient satisfaction with a high healing rate. However, the technique is associated with postoperative complications. Level of evidence : Level IV, Case series with no comparison group. Treatment study.

Evaluation of open reduction and internal fixation of proximal humerus fractures using a locking plate with smooth pegs - A retrospective study

BACKGROUND

Optimal treatment of displaced proximal humeral fractures is controversial. This retrospective study aims to identify complications and clinical outcomes using a locking plate with smooth pegs instead of screws (S3 plate).

METHOD

Eighty-two patients with displaced proximal humeral fracture classified with 2-4 fragments (Neer's classification) treated with open reduction and internal fixation (ORIF) with S3 plate were studied retrospectively. Clinical outcome according to constant score; Single Shoulder Value; Disabilities of Arm, Shoulder and Hand; and European Quality of life-5 dimensions and complication rate defined radiologically including peg penetration, avascular necrosis, and loss of reduction was assessed minimum 2.5 years after surgery.

RESULTS

A total of 11 peg penetrations were identified (13.6%). Avascular necrosis was seen in 8.5% (n = 7). Mean constant score at follow-up was 64.4 with a relative constant score of 87% (standard deviation 18%) compared to the contralateral uninjured side. The mean Disabilities of Arm, Shoulder and Hand score was 12.7 and mean European Quality of life-5 dimensions score 0.83. The mean Single Shoulder Value was 78.3. No cases of deep infection were seen.

CONCLUSIONS

Fixation with S3 plate shows a proper osteosynthesis and the functional outcome is good. Symptomatic peg penetrations are rare and the incidence is lower compared to what has been reported with locked screws.

Acute surgical treatment of acromioclavicular dislocation type V with a hook plate: superiority to late reconstruction

BACKGROUND

Outcomes for patients with acromioclavicular joint dislocation, Rockwood type V, treated with acute or delayed hook plate surgery were investigated.

MATERIALS AND METHODS

Patients treated with a hook plate for acromioclavicular joint dislocation, Rockwood type V, were retrospectively evaluated 1 to 8 years after the injury. Of 41 patients, 37 were re-evaluated, 32 in person and 5 by telephone or letter. The acute surgery group comprised 22 patients operated on with a hook plate within 4 weeks after the injury. The delayed surgery group comprised 15 patients, with unacceptable pain or functional disability after a minimum of 4 months of conservative treatment, who were operated on with modified Weaver-Dunn procedure augmented with a hook plate. The evaluation was based on radiographs, registration of activity level, and shoulder function.

RESULTS

The median Constant Score was 91 for the acute surgery group and 85 for the delayed surgery group (P = .097). The acutely treated patients had better outcomes according to the median Shoulder Pain and Disability Index (SPADI; P = .006), shortened version of the Disabilities of the Arm, Shoulder, and Hand (QuickDASH; P = .002), and Subjective Shoulder Value (P = .032). The acutely treated patients had less pain in their injured shoulder during rest (P = .014) and during movement (P = .005). There was a significant difference in subluxation between the groups in favor of the acute group, shown by weighted radiographs (P = .011), but no significant relation between subluxation on the weighted radiographs and the shoulder function according to Constant Score at follow-up (r(s) = .122, P = .619).

CONCLUSIONS

Patients treated with acute surgery had a more satisfactory outcome than those with late surgery after failed conservative treatment.

Can reverse shoulder arthroplasty be used with few complications in rheumatoid arthritis?

BACKGROUND

Many patients with rheumatoid arthritis develop superior migration of the humeral head because of massive cuff tears, causing loss of active motion. Reverse shoulder arthroplasty could potentially restore biomechanical balance but a high incidence of glenoid failure has been reported. These studies do not, however, typically include many patients with rheumatoid arthritis (RA) and it is unclear whether the failure rates are similar.

QUESTIONS/PURPOSES

We therefore (1) evaluated pain relief and shoulder function after reverse arthroplasty in RA; (2) compared results between primary and revision procedures; (3) determined the incidence of scapular notching; and (4) determined the complication rate.

METHODS

We identified 29 patients with RA who had 33 reverse arthroplasties from among 412 patients having the surgery. Six patients were lost to followup. Twenty three patients (27 shoulders) were evaluated after a minimum followup of 18 months (mean, 56 months; range, 18-143 months), including 18 primary and nine revision arthroplasties. All patients were evaluated preoperatively and 23 shoulders postoperatively by an independent physiotherapist and four were assessed postoperatively by phone. Level of pain, range of motion, and Constant-Murley score were recorded and new radiographs taken.

RESULTS

Visual Analog Scale score for pain decreased from 8.0 to 1.0. Constant-Murley score increased from 13 to 52. Primary procedures had higher scores compared with revisions. Three patients had revision surgery. Notching occurred in 52% of shoulders but no loosening was seen.

CONCLUSIONS

Reverse arthroplasty in rheumatoid arthritis improved shoulder function with a low incidence of complications. We believe it should be considered in elderly patients with rheumatoid arthritis with pain and poor active range of motion resulting from massive cuff tears.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Prosthetic overhang is the most effective way to prevent scapular conflict in a reverse total shoulder prosthesis

BACKGROUND AND PURPOSE

Despite good clinical results with the reverse total shoulder arthroplasty, inferior scapular notching remains a concern. We evaluated 6 different solutions to overcome the problem of scapular notching.

METHODS

An average and a "worst case scenario" shape in A-P view in a 2-D computer model of a scapula was created, using data from 200 "normal" scapulae, so that the position of the glenoid and humeral component could be changed as well as design features such as depth of the polyethylene insert, the size of glenosphere, the position of the center of rotation, and downward glenoid inclination. The model calculated the maximum adduction (notch angle) in the scapular plane when the cup of the humeral component was in conflict with the scapula.

RESULTS

A change in humeral neck shaft inclination from 155° to 145° gave a 10° gain in notch angle. A change in cup depth from 8 mm to 5 mm gave a gain of 12°. With no inferior prosthetic overhang, a lateralization of the center of rotation from 0 mm to 5 mm gained 16°. With an inferior overhang of only 1 mm, no effect of lateralizing the center of rotation was noted. Downward glenoid inclination of 0º to 10º gained 10°. A change in glenosphere radius from 18 mm to 21 mm gained 31° due to the inferior overhang created by the increase in glenosphere. A prosthetic overhang to the bone from 0 mm to 5 mm gained 39°.

INTERPRETATION

Of all 6 solutions tested, the prosthetic overhang created the biggest gain in notch angle and this should be considered when designing the reverse arthroplasty and defining optimal surgical technique.

Biochemical markers of bone turnover in the dairy cow during lactation and the dry period

We measured a bone-formation marker recognizing osteocalcin, and a bone-resorption marker recognizing C-telopeptide (CT(x)) fragments of collagen type I, in a longitudinal study. The levels of these markers in the plasma of dairy cows (n=11) were recorded over a 12 month postpartum period, including a full lactation and a dry period. The plasma concentration of CT(x) was highest in the first week after parturition. It then declined slowly over the next 33 weeks and remained low until the next parturition. Osteocalcin concentration was lowest around parturition, reached a plateau during mid-lactation, then fell again towards term. There were large variations in bone metabolism during a lactation, that were not directly related to milk production. These results may be used to facilitate appropriate adjustments to calcium and phosphorous concentrations in the diet, reflecting the specific needs of each stage of the reproductive cycle.

Effects of iso- and hypervolemic hemodilution on regional cerebral blood flow and oxygen delivery for patients with vasospasm after aneurysmal subarachnoid hemorrhage

BACKGROUND

Arterial vasospasm after subarachnoid hemorrhage may cause cerebral ischemia. Treatment with hemodilution, reducing blood viscosity, and hypervolemia, increasing cardiac performance and distending the vasospastic artery, are clinically established methods to improve blood flow through the vasospastic arterial bed.

METHOD

Eight patients with transcranial Doppler verified vasospasm after subarachnoid hemorrhage were investigated with global (two-dimensional (133)Xenon) and regional (three-dimensional (99 m)Tc-HMPAO) cerebral blood flow (CBF) measurements, before and after 1/iso- and 2/hypervolemic hemodilution. Hematocrit was reduced to 0.28 from 0.36. Hypervolemia was achieved by increasing blood volume by 1100 ml.

FINDINGS

Isovolemic hemodilution increased global cerebral blood flow from 52.25+/-10.12 to 58.56+/-11.73 ml * 100 g(-1) * min(-1) (p<0.05), but after hypervolemic hemodilution CBF returned to 51.38+/-11.34 ml * 100 g(-1) * min(-1). Global cerebral delivery rate of oxygen (CDRO(2)) decreased from 7.94+/-1.92 to 6.98+/-1.66 ml * 100 g(-1) * min(-1) (p<0.001) during isovolemic hemodilution and remained reduced, 6.77+/-1.60 ml * 100 g(-1) * min(-1) (p<0.001), after the hypervolemic hemodilution. As a test of the hemodilution effect on regional CDRO(2) an ischemic threshold was defined as the maximal amount of oxygen transported by a CBF of 10 ml * 100 g(-1) * min(-1) at a Hb 140 g/l which corresponds to a CDRO(2) of 1.83 ml * 100 g(-1) * min(-1). The brain volume with a CDRO(2) exceeding the ichemic threshold was 1300+/-236 ml before intervention. After isovolemic hemodilution the non-ischemic brain volume was reduced to 1206+/-341 (p<0,003). After hypervolemic hemodilution the non-ischemic brain volume remained reduced at 1228+/-347 ml (p<0.05).

INTERPRETATION

The present study of controlled isovolemic hemodilution demonstrated increased global CBF, but there was a pronounced reduction in oxygen delivery capacity. Both CBF and CDRO(2) remained decreased during further hypervolemic hemodilution. We conclude that hemodilution to hematocrit 0.28 is not beneficial for patients with cerebral vasospasm after SAH.

No effect of immunosuppression with cyclosporin A detected on bone ingrowth into cancellous allo- and xenografts in the rat

We studied the effects of the immunosuppressant cyclosporin A on bone ingrowth into allo- and xenografts in the rat using titanium bone chambers. The bone chambers were implanted bilaterally in the tibia. Each rat had one allograft and one xenograft. At 6 weeks the distance of soft tissue and bone ingrowth was measured on histological slides. In xenografts, soft-tissue ingrowth was only slightly less than in allografts, but the ingrown tissue became much less ossified. These differences were unaffected by cyclosporin A treatment, suggesting that the lesser amount of bone formation in xenografts is only weakly associated with T-cell-dependent immune reactions.

Additional colloids have only a minor haemodilutive effect after surgery for aneurysmal subarachnoid haemorrhage

Haemodilution is commonly used as prophylaxis, as well as treatment for cerebral ischaemia after aneurysmal subarachnoid haemorrhage (SAH). Thirty-six patients operated for aneurysmal SAH were evaluated retrospectively; 24 received haemodilutive therapy and 12 patients, as a control group, received no additional therapy. There was a 'spontaneous' drop in haematocrit by 22% in both groups, and a corresponding drop in haemoglobin by 23% in the treatment group and 19% in the non-haemodiluted group, during the first 4 days after the SAH. After the initial decrease the haematocrit remained stable between 0.28 and 0.33 until day 14 in both groups. The haemodilutive group had only a minor lower haematocrit level during days 8-12 as the additional fluid resulted in increased renal excretion. This minor difference was, however, significant (p < 0.02).

Arthroscopic lavage reduced the recurrence rate following primary anterior shoulder dislocation. A randomised multicentre study with 1-year follow-up

Young individuals have a high recurrence rate following non-operative treatment of traumatic primary anterior shoulder dislocation. The present multicentre study was undertaken to find out whether the results could be improved by using arthroscopic lavage as treatment. Sixty patients aged 16-30 years, with traumatic primary anterior shoulder dislocation were randomised into two groups. One group was treated with arthroscopic lavage within 10 days, while the other group was treated non-operatively. Rehabilitation was otherwise identical. At 1-year follow-up, 4 of 30 patients (13%) in the lavage group had had redislocation compared with 13 of 30 (43%) in the group treated non-operatively (P = 0.01). The difference in recurrence rate was more pronounced in younger patients. The functional outcome according to the Rowe shoulder score was better in the lavage group (P = 0.003), as was the anterior stability according to the apprehension test (P = 0.008). We conclude that arthroscopic lavage reduced the recurrence rate and produced a better functional outcome at 1-year follow-up than the non-operative treatment in young individuals.

Transcranial cerebral oximetry related to transcranial Doppler after aneurysmal subarachnoid haemorrhage

Noninvasive methods for detecting cerebral artery vasospasm, still a serious complication following aneurysmal subarachnoid haemorrhage, are of vital interest. Up-to-date transcranial Doppler ultrasound (TCD) has proved to be sensitive in detecting vasospasm in the middle cerebral artery, but has less accuracy for other cerebral arteries. Transcranial cerebral oximetry (TCCO) is a new non-invasive technique which may increase the reliability for detecting cerebral ischaemia. The purpose of the present study was to evaluate a putative correlation between TCCO and TCD. We examined the two hemispheres in 14 patients with the aim of evaluating a proposed correlation between TCD and TCCO. Analysis of all absolute values (maximum TCD mFV and minimum TCCO saturation, respectively) in all series indicate a correlation between TCCO and TCD, p < 0.01, r = -0.62. All patients with TCD mean flow velocity > 120 cm/s also presented TCCO saturation < 60%. Conversely, all patients with normal TCCO saturation (> or = 63%) presented normal or moderately increased TCD velocities. In clinical neurosurgical practice it is of great interest if a true correlation between TCD and TCCO exists. The present results support the assumption that TCCO may enhance the reliability for detecting cerebral ischaemia after aneurysmal subarachnoid haemorrhage.

Arthroscopic shoulder stabilization using transglenoid sutures

The results of arthroscopic stabilization using multiple transglenoid sutures in 24 patients with posttraumatic recurrent anterior shoulder instability are presented with a minimum follow-up of 2 years. No serious complications were recorded. There were 2 recurrences. The remaining 22 patients had good or excellent results according to the modified Rowe score, with a median score of 89. The median value for loss of external rotation was 5 degrees. Seventeen patients were active in sports and 11 returned to the same sports at the same competitive level.

[New knowledge of the mysterious "frozen shoulder". Surgical treatment can accelerate the recovery in more serious cases]

Frozen shoulder (adhesive capsulitis) affects 2-5 per cent of the population, but is most common in the 40-60-year-old age group. The disorder is divided into three phases, the painful, the stiff and the recovery phases. In most cases the condition is self-limiting with negligible residual manifestations, though its average duration is about 30 months. New findings suggest frozen shoulder to be a Dupuytren-like disorder. Pain relief and physiotherapy are usually sufficient, but in more severe cases manipulation with the patient under anaesthesia, possibly combined with distension arthrography or arthroscopic release, may yield rapid improvement in shoulder function.

Neuropeptides in heterotopic bone induced by bone matrix in immunosuppressed rats

The effects of cyclosporin A on the occurrence of neuroendocrine peptides in bone induced by demineralized allogeneic and xenogeneic bone matrix were studied in rats. Cyclosporin A enhanced bone induction in demineralized allogeneic bone matrix implants by 40% to 50% at 4 weeks, whereas there was no difference to the control group at 8 weeks. In demineralized xenogeneic bone matrix implants there was virtually no cartilage or bone formation at 4 weeks, but some bone and cartilage formation was seen at 8 weeks. In both cyclosporin A treated groups the net bone formation in demineralized xenogeneic bone matrix implants was increased four to five times at 4 weeks. Cyclosporin A treatment did not alter the temporal occurrence or distribution of neuropeptide containing nerve fibers in the bone induced by allogeneic bone matrix. Fibers containing substance P, calcitonin gene related peptide, neuropeptide Y, vasoactive intestinal peptide, and tyrosine hydroxylase were detected in the ossicles of cyclosporin A treated and control rats. In the xenogeneic bone matrix of the control group, no immunoreactive nerve fibers could be detected at 4 weeks, but at 8 weeks all five neuropeptides were detected. However, after cyclosporin A treatment immunoreactive nerve fibers could be seen at 4 weeks in the demineralized xenogeneic bone matrix implants. Thus, immunologic properties of the inductive matrix affect the yield of mineralized bone and the degree of innervation. Cyclosporin A decreases the immune response and enhances the formation of bone and the number of transmitter identified nerves in demineralized xenogeneic bone matrix induced ossicles.

Acute hemiarthroplasty after proximal humerus fracture in old patients. A retrospective evaluation of 18 patients followed for 2-7 years

We evaluated the outcome of acute shoulder hemiarthroplasty in 18 patients following displaced three- and four-part fractures of the proximal humerus. The mean age of the patients was 82 (70-92) years and the average follow-up time was 3.5 (2-7) years. No revision due to loosening was performed. All patients were evaluated concerning activities of daily living, degree of pain (VAS-scale, 0-100 mm) and range of motion. The patients had a low functional level, but were able to sleep on the operated side and keep up their hobby. 11 patients were painfree and the worst pain recorded was 28 mm. Range of motion for all movements, except extension, was statistically significant lower than for the non-operated side. We conclude that in elderly patients acute hemiarthroplasty following three- or four-part fractures of the proximal humerus results in good pain relief, but a more limited range of motion than that reported for younger patients.

Is transcranial Doppler sonography useful in detecting late cerebral ischaemia after aneurysmal subarachnoid haemorrhage?

Transcranial Doppler (TCD) examination was performed in 109 patients with aneurysmal subarachnoid haemorrhage. Fifty-seven demonstrated flow velocities exceeding 120 cm/s in the middle cerebral artery. Of these, 23 developed delayed ischaemic deficit (DID). Mean flow velocity in this group was 170, SD 12.8 cm/s, in comparison with 155, SD 11.2 cm/s in the 34 patients without late signs of cerebral ischaemia. This difference is significant (p = 0.0269). In the 34 patients without DID, but TCD > 120 cm/s, 17 received anti-ischaemic therapy based on TCD values only, while 17 were given no additional treatment. The mean TCD values and the neurological outcome in the two groups were similar. A rapid increase in flow velocities of 50 cm/s or more during a 24-h period seemed to be a strong predictor of symptomatic vasospasm as seven out of 12 patients developed DID, five with permanent neurological sequelae. The study confirms results from other centres, that a strict correlation between high TCD flow velocities and occurrence of DID does not exist.

Transcranial Doppler ultrasound in hypertensive versus normotensive patients after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Arterial hypertension is a negative prognostic risk factor after aneurysmal subarachnoid hemorrhage (SAH). Transcranial Doppler ultrasound is commonly used for measuring blood flow velocities to predict cerebral ischemia due to vasospasm after SAH. Our purpose was to evaluate the influence of arterial hypertension on blood flow velocities in the cerebral circulation after aneurysmal SAH.

METHODS

With transcranial Doppler ultrasound we compared the blood flow velocities in matched groups of hypertensive and normotensive patients with aneurysmal SAH. Twenty-four patients with arterial hypertension were examined daily during a 2-week period. As controls, 24 normotensive patients, also with SAH, were matched by age, sex, neurological status, and clinical outcome.

RESULTS

Minimum, mean, and maximum flow velocities in the middle cerebral artery in the hypertensive patients were significantly lower than in the normotensive individuals, with P = .02 for minimum, P = .02 for mean, and P = .02 for maximum. There was no statistical significance for pulsatility index differences in these groups (P = .45). Diastolic notch was noted in two of the hypertensive and in six of the normotensive patients.

CONCLUSIONS

The results indicate that even moderately increased flow velocities in hypertensive patients may represent significant vasospasm.

Trochanteric osteotomy for recurrent dislocation of total hip arthroplasty

Twenty-one patients with recurrent dislocation of total hip arthroplasty were treated by trochanteric osteotomy and distal advancement of the greater trochanter. There were no malpositioned prostheses. In 17 patients no further dislocations occurred. One patient, who had the hip arthroplasty in a paretic leg, continued to dislocate after the osteotomy and the prosthetic components were removed 5 months after surgery. The remaining three patients became stable after further surgery: cup augmentation in one and reattachment of the greater trochanter in two. Advancement of the greater trochanter is recommended in patients with recurrent dislocation of their total hip arthroplasty when no apparent malposition of the prosthetic components can be identified.

Effects of cyclosporin A on experimental new bone formation in rats

The effects of the immunosuppressive drug cyclosporin A (CsA) on bone induction by demineralized allogeneic (rat) bone matrix (DABM) and demineralized xenogeneic (rabbit) bone matrix (DXBM) were studied. Growing rats were implanted with three samples each of DABM and DXBM. Groups of eight rats were treated with 0.5 or 2 mg CsA/kg body weight for four weeks and compared with a placebo group. Cyclosporin A treatment enhanced bone induction in DABM implants by 40 to 50% at four weeks, whereas there was no difference from the control group at eight weeks. Demineralized xenogeneic bone matrix induced virtually no bone in control rats at four weeks, whereas the net bone formation increased four to five times in both groups of CsA-treated rats. At eight weeks, DXBM without CsA had induced some bone formation, and the amount was almost equal to that of DABM implants in CsA-treated groups. Also, the mineral accretion rates of DXBM were equal to DABM implants in CsA-treated rats. Cyclosporin A treatment doubled the uptake of 45Ca in the orthotopic skeleton (femora) at four weeks without affecting the mineral content, indicating an increased mineral turnover. Immunologic reactions may inhibit bone induction by DXBM, which can be counteracted by treatment with CsA.

Total hip arthroplasty in patients 80 years of age and older

One hundred fifty-seven consecutive patients (162 total hip arthroplasties) 80 years of age and older were observed for one year after total hip arthroplasty (THA). Clinical results and complications were recorded. The indication for surgery was degenerative joint disease (DJD) in one half of the patients and complications to proximal femoral fractures in the other half. The mean age was 83 years old in both groups. In 80% of the patients, no complications were recorded during the first year. Three patients died during the first three months. Two deep infections occurred (1.2%). The dislocation rate was 9.2% (15/162). There was a lower dislocation rate (4/84) in the DJD group compared to the fracture group (11/78). All nine recurrent dislocations occurred in the fracture group and were treated with either trochanteric osteotomy (five) or removal of the prosthesis (four). In the patients operated on with trochanteric osteotomy, no further dislocations occurred. The mean hospital stay was 13 days. After one year, 88% (112/127) of the patients who could be observed had good or excellent results. Total hip arthroplasty in the elderly is a reasonably safe method and yields good functional results. Dislocations, however, were common in patients operated on for complications from proximal femoral fractures, and the risk for recurrent dislocation was high (9/11). In these patients, trochanteric osteotomy is recommended.

Tissue adhesives inhibit experimental new bone formation

The effect of the cyanoacrylate tissue adhesive Histoacryl on new bone formation was studied in rats. Experimental heterotopic new bone formation was induced by implanting pieces of demineralized allogeneic bone matrix (DABM) in the abdominal wall of 10 growing Sprague-Dawley rats. This produces cartilage formation within and around the implants after 10 days, followed by enchondral ossification and the formation of an ossicle with remodelling bone and bone marrow after three weeks. Prior to implantation, the DABM-implants were treated with increasing amounts of the tissue adhesive n-Butyl-2-cyanoacrylate-monomer (Histoacryl). New bone formation was quantified at three weeks by assay of the ash content of the implants as a measure of net bone formation, by 45calcium uptake prior to sacrifice, and by histology. Treatment of DABM with the cyanoacrylate caused an intense inflammatory process with a foreign body reaction, and abolished bone induction and new bone formation. Tissue adhesives should be used with caution in fracture surgery since they inhibit new bone formation, cause a foreign body reaction, and may impede fracture healing.

Heterotopic new bone formation causes resorption of the inductive bone matrix

The bone matrix of growing rats was labeled by multiple injections of 3H-proline, and demineralized bone matrix (DBM) was prepared. The DBM was allotransplanted heterotopically into growing rats. New bone formation was induced in and around the implants. The new bone formation was accompanied by a decrease in the content of 3H; 20 and 30 days after implantation, 72% and 46%, respectively, of the activity remained in the implants. Daily injections of indomethacin (2 mg/kg) inhibited calcium uptake by about 20% at 20 and 30 days and inhibited the release of 3H from the DBM to a similar degree. Heterotopic bone induction by DBM is accompanied by matrix resorption, and inhibition of the new bone formation decreases the resorption of DBM.