JHJon E. Hammarstedt

Jon E. Hammarstedt

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Jon E. Hammarstedt has a total of 96 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Atraumatic Painful Pseudotendon of Flexor Carpi Radialis: A Literature Review and Case Report

    by Jon E Hammarstedt, William B Hogan, Jaewon Chang, Damian Slifer, Steven Regal

    Introduction: Rupture of the flexor carpi radialis (FCR) tendon is a rare phenomenon that is often described in the setting of rheumatoid arthritis or following trauma. Pseudotendon formation is seen commonly among extensor tendons of the antebrachium, typically as a sequelae of traumatic injury, spontaneous rupture in rheumatism, or postoperatively. Less frequent is the presence of pseudotendon in flexor tendons of the forearm. The development of a pseudotendon tends to result from the preservation of the tendon sheath with subsequent fibroblast proliferation. This results in a functionally deficient structure, often incapable of effective tension resistance. Case Report: We present a case of painful pseudotendon of the FCR in a patient with no identifiable common risk factors. A partial tear was identified on magnetic resonance imaging at the level of radiocarpal articulation and the patient was treated with debridement of tenosynovium and excision of the FCR tendon. The patient subsequently achieved 100% pain relief at 3 months follow-up with complete preservation of sensory and motor function and strength, and no functional complaints. We discuss the etiology of painful pseudotendon of the FCR and discuss relevant literature. Conclusion: The significance of this report stems from the evidence that pseudotendon may form through non-classical pathways idiopathically. Our case demonstrated successful removal of tenosynovium, the pseudotendon sheath and FCR tenotomy is safe, effective, and demonstrates minimal clinical deficits. Keywords: Pseudotendon, flexor carpi radialis, volar wrist pain.


  • Chronic Volar Distal Radial Ulnar Joint Dislocation

    by Jonathan Acosta, Kira Smith, Richard McKinney, Jon Hammarstedt, Steven Regal

    Case: We report the case of a 34-year-old woman with a chronic right volar dislocation of the distal radioulnar joint (DRUJ) and associated ulnar styloid fracture. The patient presented 1 month after a dog bite injury with wrist pain and limited range of motion, and radiographs demonstrated volar DRUJ dislocation. Closed reduction was unsuccessful, and thus, open reduction was performed. Conclusion: Isolated volar DRUJ dislocations in the absence of fractures are easy to misdiagnose on plain radiographs. We present our surgical technique and fixation algorithm for open reduction and stabilization for chronic volar DRUJ dislocations.


  • Return-to-Play Outcomes of Athletes After Operative and Nonoperative Treatment of Lumbar Disc Herniation

    by Shaelyn B. O’cOnnor, Kyle J. Holmberg, Jon E. Hammarstedt, Jonathan R. Acosta, Kevin Monahan, Ryan D. Sauber, Daniel T. Altman

    Purpose of Review Lumbar disc herniation (LDH) is a common injury experienced by athletes and has important clinical considerations for athletes including the timing of return to sport. Lumbar disc herniation may result in loss of individual training and playing time for athletes. Current literature is inconclusive on whether surgical or conservative treatment of LDH is superior in athletes. Our aim was to review the literature to identify return-to-play (RTP) rates and performance outcomes following operative and nonoperative treatment of LDH in the athletic population. Recent Findings Athletes have unique measurements of successful treatment for LDH such as time to return to their sport and performance outcomes that are not as applicable as traditional metrics. It is suggested that surgical treatment may provide a quicker return to sport than nonoperative care in athletes. Additionally, conflicting findings have been seen in career length and performance status based on sport, often due to short and tumultuous career patterns. These differences may be seen based on the unique physical demands of each sport, different motivations to prolong sport, or other confounding factors that could not be controlled for or unrelated to LDH. Summary Recent literature on RTP outcomes in athletes treated for LDH show variable results based on sport. Further research is needed to assist physicians and athletes in making the decision to undergo conservative or surgical treatment of LDH in the athletic population.


  • Percent articular exposure of the distal humerus with triceps fascial tongue approach compared with olecranon osteotomy

    by Nathan C. Winek, Aaron J. Rubinstein, Minju Hwang, Joseph M. Amadio, Jon E. Hammarstedt, Steven Regal


  • Biomechanical analysis of stability of joint depression calcaneal fractures: Fixation with locking compression plate alone compared with addition of supplemental oblique screw

    by Jon E. Hammarstedt, James T. Redshaw, Patrick J. Schimoler, Edward R. Westrick, Derek Andreini, Alexander Kharlamov, Mark Carl Miller


  • Open Access

    Definitive fixation of open tibia fractures: Does reopening the traumatic wound increase complication rates?

    by Alan W. Reynolds, Mariano Garay, Frances Hite Philp, Jon E. Hammarstedt, Gregory T. Altman, Chima D. Nwankwo


  • Biomechanical Analysis of Ideal Knee Flexion Angle for ACL Graft Tensioning Utilizing Multiple Femoral and Tibial Tunnel Locations

    by Jon E. Hammarstedt, J. Jared Guth, Patrick J. Schimoler, Alexander Kharlamov, Mark C. Miller, Sam Akhavan, Patrick J. Demeo

    Anterior cruciate ligament (ACL) graft failure rate has been reported to be greater than 5% at 5 years. Our study evaluated ACL excursion with anatomic and nonanatomic femoral and tibial tunnels to determine optimal flexion angle to tension the ACL to minimize excursion. Ten cadaveric knee specimens were used. The ACL was sectioned and the femoral and tibial attachments were marked. A 1/16-inch drill created a tunnel in the center of the ACL footprint on the tibia and femur and additional tunnels were made 5 mm from this. A suture was passed through each tunnel combination and attached to a string potentiometer. The knee was ranged from full extension to 120 degrees of flexion for 10 cycles while mounted in a custom fixture. The change in length (excursion) of the suture during movement was recorded for each combination of femoral and tibial tunnels. Anatomic reconstruction of the ACL with tunnel placement in the center of the femoral and tibial footprint did not result in an isometric graft, with excursion of the ACL during knee motion of 7.46 mm (standard deviation [SD]: 2.7mm), greatest at 2.84 degrees of flexion (SD: 4.22). The tunnel combination that resulted in the least excursion was a femoral footprint 5 mm anterior to the femoral and 5 mm posterior to the tibial footprint (4. 2mm, SD: 1.37 mm). The tunnel combination that resulted in the most excursion utilized femoral footprint 5 mm proximal to the femoral and 5 mm posterior to the tibial footprint (9.81 mm, SD: 2.68 mm). Anatomic ACL reconstruction results in significant excursion of the ACL throughout motion. If not tensioned properly, the ACL can stretch during range of motion, potentially leading to rerupture. To prevent stretching of the graft, the current biomechanical study recommends tensioning an anatomic ACL reconstruction at its point of maximal excursion, or between 0 and 5 degrees of flexion. The level of evidence is IV.


  • Open Access

    Pigmented Villo Nodular Synovitis as an Atypical Cause of Deep Motor Branch Neuropathy

    by Jon E. Hammarstedt, Nicholas C. Duethman, David G. Dennison

    Introduction: Compression of the ulnar nerve in Guyon’s canal results in ulnar tunnel syndrome (UTS). The patient may present with sensory and motor deficits (zone 1), motor deficit (zone 2), or sensory deficit (zone 3). The most common causes of UTS include ganglion cysts, idiopathic ulnar nerve compression, occupational pressure neuritis (repetitive compression), prolonged compression, hook of hamate fractures, and arterial thrombus or aneurysm. Case Report: We report an atypical cause of UTS involving pigmented villonodular synovitis (PVNS) with a review of the literature. Surgical decompression of the ulnar nerve at Guyon’s canal has resulted in resolving motor weakness and improved interosseous strength at latest follow-up. Conclusion: The most common causes of UTS are ganglion, occupational neuritis, prolonged compression, and ulnar artery thrombi/aneurysms. However, other more rare causes such as PVNS should be considered in the appropriate patient. Keywords: Neuropathy, ulnar nerve, ulnar tunnel.


  • Open Access

    The Loop ‘N’ Tack Biceps Tenodesis: An All‐Arthroscopic, Intra‐Articular Technique

    by Jon E. Hammarstedt, John Rinaldi, J. Jared Guth, Sam Akhavan

    Tenodesis and tenotomy of the long head of the biceps are treatment options for a wide range of pathologies without clear superior technique or site of fixation. Clinical outcomes comparing numerous techniques for tenotomy versus tenodesis have resulted in similar pain relief; however, tenotomy may result in a cosmetic “Popeye” deformity and fatigue pain. We present a quick, simple, and knotless technique for tenodesis of the long head of the biceps at the proximal aspect of the bicipital grove that can be completed entirely arthroscopically. This technique uses suture to secure a tenotomized proximal biceps tendon to a knotless anchor just proximal to the subscapularis tendon at the proximal biceps groove. The tensionless repair allows the biceps to scar within the biceps groove, thereby reducing subsidence and formation of a “Popeye” deformity and fatigue pain in the biceps seen with tenotomy alone while eliminating the ability to overtension. Technique Video: video See video under supplementary data.