Peter Jokl

Psychosocial factors and surgical outcomes: an evidence-based literature review.

Abstract The influence of psychosocial factors on clinical outcomes after surgery has been investigated in several studies. This review is limited to surgical outcomes studies published between 1990 and 2004 that include (1) psychosocial variables (eg, depression, social support) as predictors of outcome and that focus on (2) clinical outcomes (eg, postoperative pain, functional recovery) using (3) specific multivariate analytic techniques with (4) relevant clinical variables (eg, presurgical health status) included as covariates. Twenty‐nine studies met these criteria. Results indicate that psychosocial factors play a significant role in recovery and are predictive of surgical outcome, even after accounting for known clinical factors. Attitudinal and mood factors were strongly predictive; personality factors were least predictive. The results suggest that preoperative consideration of attitudinal and mood factors will assist the surgeon in estimating both the speed and extent of postoperative recovery.

A Muscle Contusion Injury Model: Biomechanics, Physiology, and Histology

We developed a reproducible muscle contusion injury and studied its effect on contractile function, histology, and passive failure. An instrumented drop-mass tech nique (mass, 171 g; height, 102 cm; spherical radius, 6.4 mm) delivered a single impact to the posterior sur face of the gastrocnemius muscle in one limb of 40 male Wistar rats. On Day 0, the impact significantly (N = 12, P < 0.01) decreased maximum tetanic tension to 63% of the contralateral control value. Histologic examina tion demonstrated extravasation of erythrocytes, edema, myofiber disruption, and vacuolation of myofi bers. Passive failure initiated at the site of injury. At 2 days, tetanic tension was 75% of controls (N = 11, P < 0.01). Histologically, acute inflammation and pha gocytosis were noted. Tetanic tension at 7 days was 81 % of controls (N = 8, P < 0.01). Vimentin staining indicated a dramatic increase in myoblast activity. Con tractile strength was near normal at 24 days. Histologic examination showed complete regeneration of normal striated muscle fibers. No vimentin activity was found. No passive failures initiated at the injury site. Contusion injury produced a significant deficit in contractile func tion that continually diminished with gross histologic evi dence of degeneration, regeneration, and normalization at the injured muscle fibers.

Implications of the pivot shift in the ACL-deficient knee

The Losee repair controls rotational subluxation of the lateral femoral condyle, or pivot shift, but does not reliably eliminate Lachman laxity. Despite this surgical limitation, many patients who were operated on continued to do high-demand activities at the last followup. We hypothesized that Lachman findings alone did not predict poor surgical outcome or progression to osteoarthritis. We report on 87 patients evaluated at an average of 9 years (range, 5-21 years) postoperatively. Prospectively collected examinations and radiographic, subjective, and objective outcome measures were recorded and statistically evaluated. The presence of a postoperative pivot shift or residual varus laxity correlated with poor patient subjective evaluations and poor scoring outcomes. Lachman laxity with an absent pivot shift had no correlation with the outcome measures or onset of radiographic progression to osteoarthritis. Meniscectomy, additional knee surgery, increased valgus or varus laxity, and time from injury until the final radiograph positively correlated with the onset of osteoarthritis. Elimination of the pivot shift was necessary to achieve successful relief of symptoms and functional outcome. In the absence of a pivot shift, Lachman laxity was not solely predictive of poor outcomes. Level of Evidence: Prognostic study, Level II-1 (retrospective study). See the Guidelines for Authors for a complete description of levels of evidence.

Muscle Contusion Injuries: Current Treatment Options

&NA; Muscle contusion is second only to strain as the leading cause of morbidity from sports‐related injuries. Severity depends on the site of impact, the activation status of the muscles involved, the age of the patient, and the presence of fatigue. The diagnosis has traditionally been one of clinical judgment; however, newer modalities, including ultrasonography, magnetic resonance imaging, and spectroscopy, are becoming increasingly important in both identifying and delineating the extent of injury. Although controlled clinical studies are scarce, animal research into muscle contusions has allowed the description of the natural healing process, which involves a complex balance between muscle repair, regeneration, and scar‐tissue formation. Studies are being performed to evaluate the effects of anti‐inflammatory medications, corticosteroids, operative repair, and exercise protocols. Prevention and treatment of complications such as myositis ossificans have also been stressed, but recognition may improve the outcome of these ubiquitous injuries.

The Effect of Anabolic Steroids and Corticosteroids on Healing of Muscle Contusion Injury

The effect of an anabolic steroid (nandrolone decanoate, 20 mg/kg) and a corticosteroid (methylprednisolone acetate, 25 mg/kg) on healing muscle injured with a drop-mass technique in a reproducible muscle contusion injury model in the rat was studied. Healing was determined by measuring active contractile tension in each muscle and histologic analysis. At day 2, the corticosteroid group showed significant improvement in both twitch and tetanic strength relative to the controls. At day 7, this effect was reversed and the corticosteroid muscles were significantly weaker than the control muscles, but there was still no significant effect seen in the anabolic steroid group. At day 14, the corticosteroid muscles were totally degenerated, with disorganized muscle fiber architecture. The anabolic steroid muscles were significantly stronger in twitch, and a similar trend was seen in tetanus relative to control muscles. The results indicate that in an animal model corticosteroids may be beneficial in the short term, but they cause irreversible damage to healing muscle in the long term, including disordered fiber structure and a marked diminution in force-generating capacity. Anabolic steroids may aid in the healing of muscle contusion injury to speed the recovery of force-generating capacity. Although anabolic steroids are considered renegade drugs, they may have an ethical clinical application to aid healing in severe muscle contusion injury, and their use in the treatment of muscle injuries warrants further research.

Muscle Contusion Injury and Myositis Ossificans Traumatica

In athletic competition, muscle contusion injury is a frequent and debilitating condition. Found in traditional contact and noncontact sports, contusions also can occur to the nonathlete by simple falls and accidents. The injury consists of a well-defined sequence of events involving microscopic rupture and damage to muscle cells, macroscopic defects in muscle bellies, infiltrative bleeding, and inflammation. The repair of the tissue can be thought of as a race between remodeling and scar formation. In the current study, the authors describe the relevant body of research directed at delineating the incidence, factors that affect injury severity, and treatment of muscle contusion injury. Emphasis is given to animal models that allow reproducible, quantitative injury, and study of the effects of various treatment modalities. Myositis ossificans traumatica, one of the most debilitating consequences of contusion injuries, also is discussed. The incidence, causative factors, and prevention strategies are reviewed.

Osteochondritis dissecans of the knee: a historical review of etiology and treatment

Osteochondritis dissecans (OCD) is a common entity in both the juvenile and adult populations, with an incidence of 3 to 6/10,000 in adults. Much of the early literature grouped juvenile and adult osteochondritis dissecans, osteochondral fracture, and accessory ossification into the same category. Conclusions were then drawn on the combined group. Nonetheless, this is a diverse group. This review discusses only OCD. There have been multiple etiological theories of OCD, ranging from trauma to ischemia to accessory centers of ossification and to genetics. It is evident that the true etiology is probably multifactorial. Bone scan, computed tomographic scan, and magnetic resonance imaging advances have enhanced the physicians ability to make the diagnosis of osteochondritis dissecans as well as to stage operative intervention. There is a vast difference between juvenile and adult OCD, as seen in the natural history, prognosis, and treatment options. In general, the juvenile patients have better results overall. The indications for operative intervention for these juvenile patients are a nonhealing attached fragment, fully or partially detached lesions of the articular surface, and loose bodies. Nonoperative treatment in the adult patient has been shown to accelerate degenerative arthritis, which involves all 3 compartments of the knee. Therefore, symptomatic lesions and loose bodies comprise the surgical indications for adult OCD. An understanding of this disease process will help the physician optimize the patients results.

MAXIMAL CONTRACTION LESSENS IMPACT RESPONSE IN A MUSCLE CONTUSION MODEL

The effect of muscle contraction on a contusion injury model was studied in the gastrocnemius muscle of anesthetized rats. Both limbs of 18 rats received a contusion injury with a blunt non-penetrating impact. One hind limb was relaxed during impact and the other was electrically stimulated to tetanic contraction. The impact was produced using a drop-mass technique (mass = 171 g, height = 101 cm, spherical radius of impactor tip = 6.4 mm). The impact response was determined by sampling (10 kHz) the transmitted impact force and the displacement of the impactor. In a subgroup of nine rats, the severity of the contusion injury was measured by recording contractile tension in twitch and tetanus within two hours of injury. We found that the peak impact force was significantly less (p < 0.01), while the peak impact displacement was significantly greater (p < 0.01) in the contracted limb. Correspondingly, the impact stiffness of the contracted limb was significantly less (p < 0.01) than the impact stiffness in the relaxed limb. Both impacts produced significant injuries relative to an uninjured control group. The tetanic tension (31 +/- 4 N) generated by the muscles that were contracted during impact was significantly (p < 0.03) greater than that generated by the muscles that were relaxed during impact (27 +/- 4 N). The findings from this specific model indicate that the impact response of the limbs with relaxed muscle was dominated by the underlying bone, while maximally contracted muscle decreased the influence of the bone and lessened the impact response. Maximally contracted muscle was not more susceptible to injury and may act as protective mechanism against some impacts.

The effect of tourniquet pressure on muscle function

The adverse effects of excessive tourniquet pressure on underlying muscle were studied using a cat model. A direct effect of the magnitude of tourniquet pressure on the degree of muscle disability was observed. The effect of direct pressure on the muscle may contribute to the postoperative weakness seen in the quadriceps muscle. Our data, in conjunction with the results of other studies that correlate certain tourniquet times and pressures with potential adverse effects, suggest that the selection of an appropriate tourniquet pressure and duration will minimize the development of clinically sig nificant complications.

Surgical Outcomes After Arthroscopic Partial Meniscectomy

Abstract Much research has been done to determine clinical and demographic variables associated with outcomes from arthroscopic partial meniscectomy for meniscal tears. We undertook a review of the literature to determine trends regarding outcomes from this procedure. Independent variables were analyzed for associations with outcome, and outcome measures and methods of statistical analysis were reviewed. Results of these studies demonstrate that patient age and sex had no significant association with any clinical or radiographic outcome variables at 8.5, 12, and 15 years. Patients with flap tears had slower return to sports and more revisions than did those with bucket handle tears. Osteoarthritis progressed more after medial partial meniscectomy in patients older than age 40 years than in younger patients. No statistically significant difference in medial versus lateral meniscectomy overall was shown. The best radiographic results in patients who underwent medial meniscectomy occurred in valgus knees compared with varus knees. Increased Modified Outerbridge cartilage scores at the time of surgery correlated with poorer physical results at 12 years.