The aim was to investigate differences of the kinetics of the crimp and the slope grip used in rock climbing. Nine cadaver fingers were prepared and fixated with the proximal phalanx in a frame. The superficial (FDS) and deep (FDP) flexor tendons were loaded selectively and together with 40 N in the crimp grip (PIP joint flexed 90°/DIP joint hyperextended) and the slope grip position (<25° flexed/50° flexed respectively). Five different grip sizes were tested and the flexion force which was generated to the grip was measured. In the crimp grip the FDP generated more flexion force in small sized holds whereas the FDS generated more force in the larger holds. During the slope grip the FDP was more effective than the FDS. While both tendons were loaded, the flexion force was always greater during crimp grip compared with the slope grip. The FDP seems to be most important for very small holds using the crimp grip but also during slope grip holds whereas the FDS is more important for larger flat holds.
Andreas Schweizer and Robert Hudek
Alison R. Valier, Ryan S. Averett, Barton E. Anderson and Cailee E. Welch Bacon
Shoulder pain is a common musculoskeletal complaint and is often associated with shoulder impingement. The annual incidence of shoulder pain is estimated to be 7% of all injuries, and is the third-most-common type of musculoskeletal pain. Initial treatment of shoulder impingement follows a conservative plan and emphasizes rehabilitation programs as opposed to surgical interventions. Shoulder rehabilitation programs commonly focus on strengthening the muscles of the shoulder complex and, more specifically, the rotator cuff. The rotator cuff is a primary dynamic stabilizer of the glenohumeral joint, using both eccentric and concentric contractions. The posterior rotator cuff, including teres minor and infraspinatus, works eccentrically to decelerate the arm during overhead throwing. Exercises to strengthen the rotator cuff and the surrounding dynamic stabilizers of the shoulder girdle vary and include activities such as internal and external rotation, full-can lifts, and rhythmic stabilizations. Traditionally, shoulder rehabilitation programs have focused on isotonic concentric contractions. Common strengthening exercises typically involve movements that result in shortening the muscle length while simultaneously loading the muscles. However, recent attention has been given to eccentric exercises, which involve lengthening of the muscle during loading, for the treatment of a variety of different tendinopathies including those of the Achilles and patellar tendons. The eccentric, or lengthening, motion is thought to be beneficial for people who are involved in activities that place eccentric stress on their shoulder, such as overhead throwers. Based on studies related to the Achilles tendon, eccentric exercise may positively influence the tendon structure by increasing collagen production and decreasing neovascularization. The changes that occur as a result of eccentric exercises may improve function, strength, and performance and decrease pain more than concentric programs, producing better patient outcomes. Although eccentric strength training has been shown to provide strength gains, there are no clear guidelines as to the inclusion of this form of exercise training in shoulder rehabilitation programs for the purposes of improving function and decreasing pain.
Focused Clinical Question:
Does adding an eccentric-exercise component to the rehabilitation program of patients with shoulder impingement improve shoulder function and/or decrease pain?
Renato Semadeni and Kai-Uwe Schmitt
In this study a numerical model of a skier was developed to investigate the effect of different rehabilitation strategies after anterior cruciate ligament (ACL) rupture.
A computer model using a combined finite-element and multibody approach was established. The model includes a detailed representation of the knee structures, as well as all major leg muscles. Using this model, different strategies after ACL rupture were analyzed.
The benefit of muscle training to compensate for a loss of the ACL was shown. The results indicate that an increase of 10% of the physiological cross-sectional area has a positive effect without subjecting other knee structures to critical loads. Simulating the use of a hamstring graft indicated increasing knee loads. A patellar-tendon graft resulted in an increase of the stress on the lateral collateral ligament.
Muscle training of both extensors and flexors is beneficial in medical rehabilitation of ACL-deficient and ACL-reconstructed knees.
Michael R. McCarthy, Barton P. Buxton, W. Douglas B. Hiller, James R. Doyle and Denis Yamada
In an attempt to quantify the current standards in surgical procedures and rehabilitation protocols utilized to treat patients with anterior cruciate ligament (ACL)-deficient knees, a 19-question survey was sent to members of the Hawaii Orthopedic Association. The findings indicated that only 54% (30/56) of the respondents were performing ACL reconstructions, of which 87% (26/30) were performing an intra-articular procedure and none were performing extra-articular procedures exclusively. The findings further indicate that 80% (24/30) of the 30 respondents performing ACL reconstructions were using an arthroscopically assisted, bone-tendon-bone autograft procedure. However, in marked contrast to the uniformity that existed concerning the surgical procedure, there was a drastic difference in the rehabilitation protocols and procedures that were recommended postoperatively. The most apparent differences in rehabilitation protocols existed in the utilization and initiation of open versus closed type kinetic chain exercises and activities.
Joseph B. Myers
Shoulder pain is a common complaint among overhead athletes. Oftentimes, the cause of pain is impingement of the supraspinatus, bicipital tendon, and subacromial bursa between the greater tuberosity and the acromial arch. The mechanisms of impingement syndrome include anatomical abnormalities, muscle weakness and fatigue of the glenohumeral and scapular stabilizers, posterior capsular tightness, and glenohumeral instability. In order to effectively manage impingement syndrome nonoperatively, the therapist must understand the complex anatomy and biomechanics of the shoulder joint, as well as how to thoroughly evaluate the athlete. The results of the evaluation can then be used to design and implement a rehabilitation program that addresses the cause of impingement specific to the athlete. The purpose of this article is to provide readers with a thorough overview of what causes impingement and how to effectively evaluate and conservatively manage it in an athletic population.
Allyson M. Carter, Stephen J. Kinzey, Linda F. Chitwood and Judith L Cole
Proprioceptive neuromuscular facilitation (PNF) is commonly used before competition to increase range of motion. It is not known how it changes muscle response to rapid length changes.
To determine whether PNF alters hamstring muscle activity during response to rapid elongation.
2 X 2 factorial.
Twenty-four women; means: 167.27 cm, 58.92 kg, 21.42 y, 18.41% body fat, 21.06 kg/m2 BMI.
Measurements before and after either rest or PNF were compared.
Main Outcome Measures:
Average muscle activity immediately after a rapid and unexpected stretch, 3 times pretreatment and posttreatment, averaged into 2 pre-and post- measures.
PNF caused decreased activity in the biceps femoris during response to a sudden stretch (P = .04). No differences were found in semitendinosus activity (P = .35).
Decreased muscle activity likely results from acute desensitization of the muscle spindle, which might increase risk of muscle and tendon injury.
Scott M. Lephart, Mininder S. Kocher, Freddie H. Fu, Paul A. Borsa and Christopher D. Harner
Injury to the anterior cruciate ligament (ACL) is thought to disrupt joint afferent sensation and result in proprioceptive deficits. This investigation examined proprioception following ACL reconstruction. Using a proprioceptive testing device designed for this study, kinesthetic awareness was assessed by measuring the threshold to detect passive motion in 12 active patients, who were 11 to 26 months post-ACL reconstruction, using arthroscopic patellar tendon autograft (n=6) or allograft (n=6) techniques. Results revealed significantly decreased kinesthetic awareness in the ACL reconstructed knee versus the uninvolved knee at the near-terminal range of motion and enhanced kinesthetic awareness in the ACL reconstructed knee with the use of a neoprene orthotic. Kinesthesia was enhanced in the near-terminal range of motion for both the ACL reconstructed knee and the contralateral uninvolved knee. No significant between-group differences were observed with autograft and allograft techniques.
George Forrest and Kurt Rosen
Ultrasound is a commonly used modality of deep heating. Two techniques of application have been recommended: a technique in which the applicator head is applied directly to the subject and an immersion technique, The purpose of this study was to determine whether ultrasound treatments using the immersion technique in degassed water are as effective as ultrasound treatments using the direct technique of application in raising the temperature of periarticular structures into the therapeutic range. The limbs of a pig were treated with the direct and immersion techniques of application. Temperatures of the skin surface and of the extensor tendons of the ankle were taken before and after both methods of application. Treatments with the applicator head in direct contact with the limb of the subject were the more effective form of heating.
Kevin E. Wilk, James R. Andrews, William G. Clancy Jr., Heber C. Crockett and James W. O'Mara Jr.
Treatment of posterior cruciate ligament (PCL) injuries has changed considerably in recent years. This article discusses current rehabilitation for PCL disruptions in athletes. The treatment of PCL injuries varies somewhat based on the chronicity (acute vs. chronic) of injury and associated pathologies. The authors provide their treatment algorithm for the acute and chronic PCL-injured-knee patient. Nonoperative rehabilitation is discussed with a focus on immediate motion, quadriceps muscle strengthening, and functional rehabilitation. A discussion of the biomechanics of exercise is provided, with a focus on tibiofemoral shear forces and PCL strains. Surgical treatment is also discussed, with the current surgical approach being either the two-tunnel or the one-tunnel patellar tendon autograft procedure. The rehabilitation program after surgery is based on the healing constraints, surgical technique, biomechanics of the PCL during functional activities, and exercise. With the new changes in surgical technique and in the rehabilitation process, the authors believe that the outcome after PCL reconstruction will be enhanced.
Mark S. De Carlo, Kecia E. Sell, K. Donald Shelbourne and Thomas E. Klootwyk
It is well established that intra-articular anterior cruciate ligament reconstruction with autogenous bone-patellar tendon-bone graft provides satisfactory long-term stability. However, the rehabilitation programs employed following this surgical procedure have been a topic of considerable debate. This paper describes an accelerated rehabilitation protocol that is divided into four phases. The first phase encompasses the preoperative period, during which the patient will work to decrease swelling and restore range of motion and strength. The second phase involves Weeks 1 and 2 following surgery, with the patient emphasizing immediate terminal knee extension and weight bearing. The final two phases involve improving lower extremity strength and full return to daily and athletic activities. This accelerated rehabilitation protocol has resulted in an earlier return of range of motion and strength without compromising ligamentous stability.