Changes in biomechanical risk factors for knee osteoarthritis and their association with 5-year clinically important improvement after limb realignment surgery.

OBJECTIVE: To evaluate 5-year outcomes after lower limb realignment and test the hypothesis that surgery-induced changes in selected biomechanical risk factors for medial knee osteoarthritis (OA) are associated with clinically important improvements. DESIGN: We prospectively evaluated patient-reported outcomes, full-limb standing radiographs and gait biomechanics before, 6 months (surgery-induced change) and 5 years after medial opening wedge high tibial osteotomy (HTO) in 170 patients (46.4 ± 8.9 years, 135 males) with knee OA and varus alignment. Logistic regression tested the associations of 6-month changes in mechanical axis angle and knee adduction moment with achieving an increase of ≥10 points in the Knee injury and Osteoarthritis Outcome Score (KOOS)4 at 5 years, with and without adjusting for covariates. Gait data were also compared to existing data from healthy controls. RESULTS: Mean 5-year changes (95% confidence interval (CI)) were: KOOS4: +14.2 (10.8, 17.6); mechanical axis angle: +8.21° (7.58, 8.83); knee adduction moment: -1.49 %BW*Ht (-1.35, -1.63). The postoperative knee adduction moments were typically lower than values for healthy controls. When divided into quartiles, although all strata improved significantly, patients with reductions in knee adduction moment of 1.14-1.74 %BW*Ht (neither largest nor smallest changes) had highest 5-year KOOS4 scores. The 6-month change in knee adduction moment (odds ratios (OR) = 0.38; 95% CI: 0.22, 0.67), preoperative KOOS4 (OR = 0.96; 95% CI: 0.94, 0.99) and preoperative medial tibiofemoral narrowing grade (OR = 0.62; 95% CI: 0.37, 1.00) were negatively associated with having a 5-year clinically important improvement (C-statistic = 0.70). CONCLUSIONS: Substantial improvements in biomechanical risk factors and patient-reported outcomes are observed 5 years after medial opening wedge HTO. The surgery-induced change in load distribution during walking is significantly associated with long-term clinically important improvement.

High tibial osteotomy: evolution of research and clinical applications--a Canadian experience.

PURPOSE: This narrative review describes experiences at the Fowler Kennedy Sport Medicine Clinic (FKSMC) with high tibial osteotomy (HTO) for patients with varus gonarthrosis, with particular focus on research published from the unit that has guided practice. METHODS: The goals of surgery are to improve alignment of the weight bearing axis of the lower limb to lessen the load on the medial tibiofemoral compartment and thereby decrease these important risk factors for disease progression. The overall aims are to improve knee function and delay or even prevent the eventual need for arthroplasty. To achieve these aims, a medial opening wedge osteotomy is utilised, deliberately avoiding an over correction of the lower limb, but tailoring the angle of correction to an individual patient's characteristics. With such an approach, patients with a broad range of characteristics (including age, BMI and lateral compartment involvement) can benefit from the procedure. In addition, the HTO can be used with concomitant procedures to address specific presentations, such as large deformities and instability. RESULTS: The results suggest that correction to a slight valgus alignment produces approximately 50% reduction in medial compartment loads during gait with large, clinically important improvements in patient-reported outcomes at 2-years postoperatively. In patients with substantial bilateral varus deformity, unilateral surgery can lead to increased dynamic knee joint loads on the nonoperative limb after surgery. This means that such patients require the close monitoring of both limbs and consideration of a staged, bilateral procedure if necessary. In patients requiring bilateral surgery, similar results after bilateral HTO to those after unilateral surgery have been reported. For patients requiring large corrections, the need for a concomitant tibial tubercle osteotomy to reduce the potential for iatrogenic patella infera is considered. Finally, HTO procedures can also be used in patients with instability, either to alter both sagittal and coronal alignment to correct instability in complex ligament deficiencies or to undertake simultaneous HTO and ACL reconstruction. CONCLUSIONS: HTO is being used both alone and in conjunction with concomitant procedures with good clinical results. While continued investigation into patient selection and outcomes are required, current research indicates that HTO offers at least a partial solution for the patient with varus gonarthrosis to prolong the life of their native knee joint. LEVEL OF EVIDENCE: V.

A very unusual case history.

The above case history demonstrates well how a severe potentially lethal medical condition can often develop quite insidiously with what appeared to be quite common and everyday symptoms initially. In my opinion, one of the potential problems with the management of this lady was the number of different doctors she consulted within the practice, both military and locum (11 in total during 2007) resulting in lack of continuity of case. However, it is impossible to ascertain quite when the vasculitis actually developed or whether it could have been suspected earlier. In nearly 30 years as a doctor, this is the first case of Wegener's that I have knowingly come across. Perhaps because of such rarities, this is what makes being a GP such an interesting and challenging role. So next time you see someone with a runny nose and dry cough .... think again!

Exercise Maganga Mercury 23 January-10 February 2006.

It is very likely that Royal Navy doctors will be called upon more and more in the future to work on similar overseas exercises. I found the experience immensely challenging and educational and would have no hesitation in volunteering for further deployments or recommending other RN doctors to do the same.

1,3-Diaryltriazenes: a new class of anorectic agents.

A series of substituted 1,3-diaryltriazenes has been synthesized and tested for anorectic activity. Several members of the series were effective; one compound, 1,3-bis[2-cyano-5-(trifluoromethyl)phenyl]triazene, was particularly active, causing weight loss in rats, dogs, and squirrel monkeys. It was devoid of overt central nervous system activity, and compared to previously reported biologically active triazenes, it was relatively nontoxic up to 30 days of drug administration.

Subchondral bone infractions in acute ligamentous knee injuries demonstrated on bone scintigraphy and magnetic resonance imaging.

Bone scintigraphy is used to detect radiographically silent fractures. Magnetic resonance imaging (MRI) is currently used to screen knee injuries for cartilage and ligament damage. MRI also delineates bone marrow and fractures. We investigated the bone scintigraphic findings in patients who had subchondral bone injuries demonstrated on MRI. Thirteen patients underwent MRI, three-phase bone scintigraphy with SPECT, and arthroscopic surgery after sustaining acute traumatic hemarthrosis of a knee. They all had clinically unsuspected subchondral bone injuries demonstrated on MRI with normal radiographs and normal overlying articular cartilage at arthroscopy, consistent with occult fractures. All showed focal bone repair on scintigraphy. Two of the 13 patients showed additional bone injuries only on bone scan. Two other patients scintigraphically showed focal bone repair at the medial femoral condyle due to avulsion of the medial collateral ligament. SPECT was easier to interpret than multi-view planar imaging. Bone scintigraphy confirms subchondral fractures demonstrated on MRI but also demonstrates ligament avulsion injuries and additional more subtle bone injuries.

Effects of KC 2450 on the lower esophageal sphincter in vivo and in vitro.

The effect of KC 2450 (racemic 3,5-cis-3-methylamino-2,3,4,5-tetrahydro-1-benzoxepine-5-ol hydrochloride) on lower esophageal sphincter pressure in pentobarbital-anesthetized dogs was determined and compared to the effect of metoclopramide. The ED20 value (i.e. the dose that increased lower esophageal sphincter pressure 20 mm Hg) was 0.72 (0.45-1.04) mg/kg i.v. for KC 2450, significantly different from 2.18 (1.30-3.42) mg/kg i.v. for metoclopramide (P less than 0.01). The superior potency of KC 2450 over metoclopramide also was demonstrated at a dose of 2 mg/kg i.v.; KC 2450 produced an increase in sphincter pressure of 43.2 +/- 4.4 mm Hg and metoclopramide produced an increase in sphincter pressure of only 28.5 +/- 5.4 mm Hg (P less than 0.05). Intraduodenally administered KC 2450 increased lower esophageal sphincter pressure at a threshold dose of 2 mg/kg with 10 mg/kg producing an increase in pressure of 53.2 +/- 9.9 mm Hg. KC 2450-induced increases in sphincter pressure were not affected by bilateral cervical vagotomy or ketanserin, but were eliminated by atropine and reduced by neuronal blockade using tetrodotoxin (TTX). KC 2450 effects also were determined in isolated circular strips of lower esophageal sphincter muscle. KC 2450 produced a concentration-related increase in canine (EC50 = 27 microM) and opossum (EC50 = 199 microM) sphincter muscle strip tension. The KC 2450 concentration-response curve was antagonized by atropine in canine and opossum sphincter muscle strips. Neuronal blockade of canine sphincter muscle with TTX antagonized the KC 2450 concentration-response curve in a non-competitive manner.(ABSTRACT TRUNCATED AT 250 WORDS)

The surgical treatment of exertional compartment syndrome in athletes.

We studied the cases of twelve patients who had bilateral exertional compartment syndrome involving one or all of the compartments of the lower extremities. The patients were divided into three groups based on the clinical findings. Group I consisted of seven patients with symptoms involving the anterior or lateral compartments only; Group II, of three patients with involvement of the deep posterior compartments alone; and Group III, of two patients with involvement of both the anterior and deep posterior compartments. On the basis of their clinical signs and symptoms each patient underwent dynamic tissue-pressure measurements using a slit catheter before, during, and for as long as thirty minutes after exercise. All patients had elevated resting and peak-to-peak dynamic pressure measurements. Treatment consisted of bilateral compartmental fasciotomy, as indicated. All of the patients in Group I had complete relief of symptoms; however, one patient in Group II and one in Group III had a recurrence of symptoms in the deep posterior compartment.

Release of the subscapularis for internal rotation contracture and pain after anterior repair for recurrent anterior dislocation of the shoulder.

Ten patients who had an internal rotation contracture and pain after an anterior repair for recurrent dislocation of the shoulder were treated by release of the subscapularis muscle. For six of the patients, radiographs demonstrated severe osteoarthrotic changes in the shoulder as well. The release was done an average of eleven years after the original procedure, which, for most patients, had been a Putti-Platt repair. After release of the subscapularis, each patient had less pain in the shoulder and an average increase of 27 degrees of external rotation. Release of the subscapularis can offer relief of pain and of functional limitations associated with the symptoms caused by an internal rotation contracture after an anterior repair of the shoulder.

Isolated posterior cruciate ligament injuries in athletes.

The literature is divided as to the necessity of an intact posterior cruciate ligament for functional stability. Presented here is a prospective study of isolated posterior cruciate injuries seen in the acute stage in 13 patients, 6 males and 7 females. The diagnosis of posterior cruciate ligament tear was made clinically and confirmed by arthroscopy. The average age at injury was 22 years. The athletic activity at injury was varied. Hyperflexion was the most common mechanism of injury, followed by pretibial trauma in the hyperflexed knee or in the "dashboard" injury. There were seven complete midsubstance tears and five partial tears. Direct visualization of the posterior cruciate ligament was not attained in one patient. All patients were treated nonoperatively on a physiotherapy routine. Average followup was 2.6 years. Patients were clinically examined and subjected to KT-1000 and Cybex testing. All patients were able to return to their previous activity and experienced no limitations with their injured knees. Using Hughston's criteria, subjective and functional ratings were all good. However, only 3 rated good and 10 fair when assessed objectively. We conclude that acceptable functional stability in these patients does not necessarily require absolute static stability. Nonoperative treatment of the isolated posterior cruciate ligament midsubstance injury may be a viable alternative to the difficult repair/reconstruction procedure.

The patient with symptomatic chronic anterior cruciate ligament insufficiency. Results of minimal arthroscopic surgery and rehabilitation.

Forty-nine patients with 51 chronic symptomatic anterior cruciate deficient knees were studied retrospectively by chart review and follow-up examination an average of 5.8 years postinjury and 1.5 years from arthroscopic evaluation, with or without arthroscopic surgery, and the institution of a conservative rehabilitation program. Subjective evaluation of function was obtained by questionnaire. At arthroscopy, meniscal lesions were seen in 37 of 51 knees, and degenerative changes were noted in 24 knees. The ACL was absent in 43 knees. Partial meniscectomy or suturing was performed on 20 patients. All patients had an average of 3 weeks of supervised physical therapy stressing hamstring strengthening. At followup, thigh girth measurements of injured and normal legs found thigh wasting in 40 patients. Seven of 33 patients radiographed showed evidence of degenerative changes. About two-thirds of the patients returned to some level of athletics and had no problems with activities of daily living. Twenty were able to return to pivoting sports, but only five could return to their preinjury levels of competition. Of the 18 patients who did not return to athletics, only 8 were considering or had had a ligament reconstruction. Those patients who chose to continue rehabilitation beyond the prescribed period and who modified their activities had a better functional outcome.

The anterior horn of the medical meniscus. An anatomic study of its insertion.

A morphologic study of 48 cadaveric knees was performed to more accurately define the osseous and soft tissue anatomy of the insertion of the anterior horn of the medial meniscus. Soft tissue relationships of the anterior horn of the medial meniscus to the anterior cruciate ligament and the lateral meniscus were examined. Four tibial insertion locations of the medial meniscus were identifiable by bony landmarks. Type I insertions were located in the flat intercondylar region of the tibial plateau; type II occurred on the downward slope from the medial articular plateau to the intercondylar region; type III occurred on the anterior slope of the tibial plateau; there was no firm bony insertion of the anterior horn in type IV. The occurrence for type I was 59% (20 of 34); type II, 24% (8 of 34); type III, 15% (5 of 34); and type IV, 3% (1 of 34). The variance in insertion patterns may have clinical applications for patients with atypical anterior knee pain and for performing meniscal allograft. Type III and type IV insertions may be unable to resist peripheral extrusion of the loaded meniscus, placing it at risk for anterior subluxation and causing anterior knee pain in specific cases. Awareness of these patterns may be valuable in medial meniscus harvest and transplantation.

Anatomy of the posterior cruciate ligament. A review.

PCL injuries are major injuries of the knee. Most of the literature on PCL injury has focused on mechanism of injury, diagnosis, and treatment. We are presenting a review of the anatomy of the PCL. Different portions of the PCL are taut at different degrees of knee flexion and extension. The PCL, thus, along with the ACL, contributes to the "screwhome mechanism" of the knee. The anatomy of the meniscofemoral ligaments (ligaments of Wrisberg and Humphrey) reveals the intimate relationship among the PCL, the popliteus muscle, and the lateral meniscus. Understanding the anatomy of the PCL is important in the diagnosis and treatment of ligamentous injuries and also in total knee arthroplasty.

The results of fasciotomy in the management of chronic exertional compartment syndrome.

Twenty-five patients with well-documented clinical history and elevated tissue pressures were subjected to surgical fasciotomy of the respective compartment (anterior, 13; anterior and posterior, 4; deep posterior, 8). The indications for surgery were resting pressures in excess of 15 mmHg and elevated postexercise pressure measurements with delayed normalization. Twenty-two patients were satisfied with the procedure and were able to return to athletics. There were three failures, all of whom had decompression of the deep posterior compartment. This study has demonstrated that fasciotomy of the anterior compartment, when done with the correct indications, gives excellent relief of chronic anterior leg pain. It is recommended that fasciotomy of the deep posterior compartment include a formal release of the tibialis posterior at the time of decompression.

Functional postoperative treatment of Achilles tendon repair.

Twenty-one patients with surgically repaired Achilles tendon tears that were treated postoperatively with a functional orthosis rather than routine cast immobilization were evaluated. The orthosis allowed unrestricted plantar flexion and limited dorsiflexion to neutral. Toe-touch weightbearing crutch ambulation was allowed immediately and was gradually increased over the 6 to 8 weeks of treatment. Of the 21 patients, 14 were men and 7 were women; the average age at injury was 35.6 years (range, 19 to 65). The minimum followup was 2 years, with an average of 31 months. The repairs were acute in 18 of the patients and chronic in 3. Subjectively, 16 patients felt they returned to their preinjury level of activity and only 1 was not satisfied with his result. Objectively, there were no significant alterations in ankle range of motion when compared to the contralateral limb, with plantar flexion unchanged and dorsiflexion increased an average of only 2 degrees. The average plantar flexion and dorsiflexion strength, power, and endurance of the ankles as measured by isokinetic testing revealed no significant differences when comparing the operated leg to the nonoperated side: strength, 99% and 93%, respectively; power, 98% and 96%, respectively; and endurance, 93% and 91%, respectively. The angles at which the peak torques occurred were similarly not statistically different. Two patients had superficial wound infections, and 1 had scar adherence of the skin to the tendon. No one had rerupture of the tendon. In conclusion, while the many benefits of postoperative early motion are well proven, there has been hesitation to implement this after Achilles tendon surgery due to the concern of compromising the repair. As shown by this study, early controlled motion can safely and effectively be used following Achilles tendon repair in the motivated, reliable patient.

Limitation of motion following anterior cruciate ligament reconstruction. A case-control study.

Limitation of motion following ACL reconstruction is a well-recognized and disturbing complication. The purposes of this study were to identify and characterize those patients who developed this complication from a series of 527 ACL reconstructions, determine etiologic factors, and make recommendations regarding prevention and management. The case group included 37 patients who required a manipulation under anesthesia because of failure to gain a satisfactory range of motion after an ACL reconstruction. Unsatisfactory motion was defined as a flexion deformity of 10 degrees or more and/or limitation of flexion to less than 120 degrees by 3 months following ACL reconstruction. The control group of patients were selected randomly from the overall series and all had a satisfactory range of motion. The cases and controls were then compared by analyzing these variables: age, sex, knee, time from injury to reconstruction, type of tissue used, meniscal abnormalities or surgery, repair of the medical collateral ligament, and postoperative immobilization and rehabilitation. The cases were followed up to assess the range of motion compared to the opposite knee at an average of 26 months postmanipulation. Thirty-seven patients (7%) underwent a manipulation under anesthesia, 9 of these (24.3%) also had an arthroscopic arthrolysis. Reconstructions done less than 2 weeks postinjury showed a statistically significant higher rate of knee stiffness. The same trend was also present for those reconstructed 2 to 6 weeks postinjury. All other variables failed to show a significant statistical difference. At followup, the average loss of extension was 4 degrees and loss of flexion 5 degrees.(ABSTRACT TRUNCATED AT 250 WORDS)

The tibialis posterior muscle compartment. An unrecognized cause of exertional compartment syndrome.

Exertional compartment syndrome in the deep posterior compartment of the leg is well recognized. This paper reports investigations which were performed to prove that the tibialis posterior muscle is contained in its own osseofascial compartment, separate from the rest of the deep posterior compartment. Radiographs following the injection of radio-opaque dye into the tibialis posterior muscle demonstrated the fluid-impermeable, osseofascial boundaries surrounding this muscle. Compartment syndromes created in cadaver legs reveal that traditional techniques of fasciotomy of the deep posterior compartment are inadequate in decompressing the tibialis posterior muscle. Intracompartmental pressure measurements in athletes with a clinical diagnosis of exertional compartment syndrome proved the existence of isolated exertional compartment syndrome in the tibialis posterior muscle. From these results we may conclude that the tibialis posterior muscle is contained in a separate osseofascial muscle compartment which may be the site of an isolated exertional compartment syndrome and that common techniques of fasciotomy of the deep posterior compartment do not decompress the tibialis posterior muscle.

The effect of cast immobilization on meniscal healing. An experimental study in the dog.

A 1.5-cm longitudinal, full-thickness incision was made in the vascularized portion of the medial meniscus in 20 adult dogs and anatomically repaired. Postoperatively, the animals were either placed in a long leg cast (N = 9) or mobilized immediately (N = 11). The animals were sacrificed at 2 weeks (6 dogs), 4 weeks (6 dogs), or 10 weeks (8 dogs). Five medial menisci from the nonoperated side were used as controls. Collagen content was measured using a digital image analysis system, and the collagen percentage in the repair tissue in each postoperative treatment group was compared. In the 2-week and 4-week groups, there was no statistically significant difference in the percentage of collagen between those animals immobilized versus those that had early mobilization. The animals in the 10-week group that were mobilized had a significantly greater collagen percentage in the healing meniscal incision than those that were cast immobilized (44.6% +/- 10% versus 27.0% +/- 11%, P < 0.0001). There was no significant difference in the collagen percentages between the mobilized 10-week group and the contralateral control menisci group. All other menisci had a decreased collagen percentage compared with the controls. Prolonged immobilization decreases collagen formation in healing menisci. Thus, our results suggest that patients undergoing isolated meniscal repair either be immediately mobilized after surgery or immobilized for short periods only.

Occult osteochondral lesions after anterior cruciate ligament rupture. Six-year magnetic resonance imaging follow-up study.

Twenty-three patients with acute anterior cruciate ligament injuries, normal radiographs, and occult osteochondral lesions revealed by magnetic resonance imaging were reviewed 6 years after initial injury and anterior cruciate ligament hamstring autograft reconstruction. Each patient completed the Mohtadi Quality of Life outcome measure for anterior cruciate ligament deficiency, underwent clinical examination, and had a repeat magnetic resonance imaging scan. The index and follow-up magnetic resonance imaging scans were compared with respect to cartilage thinning and marrow signal. A significant number of patients had evidence of cartilage thinning adjacent to the site of the initial osteochondral lesion. Marrow signal changes persisted in 15 (65%) of the patients. Clinical comparison of patients with normal cartilage with those who had cartilage thinning revealed similar results on both KT-1000 arthrometry and on the Mohtadi outcome measure. This suggests that the initial injury resulted in irreversible changes in the knee. Injuries causing marrow signal changes may result in an alteration in the load-bearing properties of subchondral bone, which in turn allow for changes in the overlying cartilage. Further follow-up will determine the clinical significance of changes detected by magnetic resonance imaging.

Comparative functional analysis of the Bristow, Magnuson-Stack, and Putti-Platt procedures for recurrent dislocation of the shoulder.

Literature on anterior shoulder instability deals most often with elimination of recurrence following reconstruction. We analyzed the subjective function, loss of motion and shoulder strength of three operative procedures: Magnuson-Stack, Bristow, and Putti-Platt. A retrospective review of 27 patients, 9 in each surgical group, with no postoperative dislocations or on-going pain was performed. All patients were male, right hand dominant with the right shoulder affected. Average time of followup was 6.75 years (range, 4.2 to 10.3 years). All patients completed a questionnaire and had their range of motion measured by a hand-held goniometer and their shoulder strength tested on the Cybex II Dynomometer. Peak torque as a percent of body weight and side-to-side differences were calculated for six arm positions and compared to nine right hand dominant controls of similar age and recreational activity. Sixty percent returned to throwing sport. One Magnuson-Stack and Bristow patient felt full functional return to preinjury level. Three patients in each of these two groups returned to unmodified throwing sport whereas no Putti-Platt patient attained this level. Deficit of external rotation at shoulder neutral measured 4.7 degrees, Magnuson-Stack; 12.2 degrees, Bristow; and 21.8 degrees, Putti-Platt. At 90 degrees shoulder abduction, similar deficits in external rotation measured 6.4 degrees, 11.6 degrees, and 28.8 degrees respectively. These values were statistically significant employing analysis of variance. We compared the operative groups as a whole to the controls and compared the operative groups to each other.(ABSTRACT TRUNCATED AT 250 WORDS)