A 66 year-old man presents with right anterior elbow pain, ecchymosis, and a “lump” in his right upper extremity after a ground level fall (Figure 1). What is your suspected diagnosis? What physical exam maneuver(s) can help you confirm your diagnosis? What is your initial workup in the ED? What imaging confirms the diagnosis? What is your management and disposition?
Pearl: In a patient following a traumatic event with elbow ecchymoses and an appreciable deformity near the upper extremity, in this case reported as a “lump”, a distal biceps rupture must be in the differential.
A complete distal biceps rupture is largely a clinical diagnosis based on the mechanism of injury (strong, mechanical overload during eccentric muscle contraction of the biceps) as well as a positive hook test and Yergason’s test. However, X-ray of the elbow can help rule out fracture, especially given an atypical mechanism of injury, such as in our patient.
Pearl: Bedside ultrasound is helpful in the hands of a skilled operator, as imaging of the distal biceps with other modalities can be difficult (Figure 2).
Figure 2: Image A: Ultrasound distal biceps (tendon rupture with appreciated tendon incongruity and retraction towards left part of image), Case Courtesy of Dr. Maulik S. Patel, Radiopaedia.org, rID: 61870; Image B: Ultrasound Distal Biceps (Normal evaluation with intact, compact distal biceps tendon), Case Courtesy of Dr. Maulik S. Patel, Radiopaedia.org, rID: 61870; Image C: Probe placement for evaluation distal biceps in long-axis view (Case Courtesy of Dr. Peter M. Martin)
Imaging is not necessary to confirm a distal biceps rupture . If needed however, such as in preoperative evaluation, this can be performed by diagnostic ultrasound or MRI (Figure 3). MRI is usually obtained on an outpatient basis. When performed, it should be done soon after discharge from the ED, ideally within 1-2 weeks, as best surgical outcomes are obtained when surgery is performed within 2-3 weeks of injury occurrence [2,3].
Figure 3: Proton Density Fat-Saturated (PD FS) sequence at the level of the radial tuberosity (Insertion point of the conjoint distal biceps tendon shows hemorrhage and edema at the insertion, and lack of visualization of the tendon). There is also edema and hemorrhage between the fascial planes of the brachioradialis and pronator teres, and edema within the superficial soft tissues (Case courtesy of Dr. Peter M. Martin).
While proximal biceps injuries and tears may be managed conservatively initially, complete distal biceps tears warrant timely surgical intervention for most patients (except for the most low demand and sedentary patients). These injuries need to be operated on within 2-3 weeks of the injury for best outcomes with regards to strength and appreciable muscle deformity . Therefore, patients should have urgent follow up with orthopedic surgery. No bracing or casting is needed.
Tarallo, L., Lombardi, M., Zambianchi, F. et al. Distal biceps tendon rupture: advantages and drawbacks of the anatomical reinsertion with a modified double incision approach. BMC Musculoskelet Disord 19, 364 (2018). PMID: 30305070.
García Rodríguez C, García-Polín López C, Del Olmo Hernández T, Moros Marco S, Jacobo Edo O, Ávila Lafuente JL. Distal biceps tendon rupture: diagnostic strength of ultrasonography and magnetic resonance. Rev Esp Cir Ortop Traumatol (Engl Ed). 2020 Mar-Apr;64(2):77-82. English, Spanish. doi: 10.1016/j.recot.2019.11.004. Epub 2020 Jan 27. PMID: 32001186.
Logan CA, Shahien A, Haber D, Foster Z, Farrington A, Provencher MT. REHABILITATION FOLLOWING DISTAL BICEPS REPAIR. Int J Sports Phys Ther. 2019 Apr;14(2):308-317. PMID: 30997282; PMCID: PMC6449020.