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Hook of Hamate Excision

25 citationsUpdated Sep 2026
Illustration: wrist

For patients: a plain-language version of this topic is available. See the patient guide.

Overview

Surgical excision of hook of hamate fractures is a safe and effective management strategy for both acute and chronic injuries, particularly in professional baseball players [4]. The procedure is associated with a low risk of minor complications and allows for a relatively rapid return to play in most cases [2, 14]. In elite baseball players, the rate of return to play within six weeks is very high [7, 10]. A systematic review and meta-analysis documented return to play for 94.5% (778/823) of patients undergoing treatment for hook of hamate fractures [11].

Outcomes in professional baseball players following surgical excision include an 84% return to sport, with 81% returning to the same or higher level of play [9]. MLB players can reasonably expect to return to their pre-injury performance levels following operative treatment [15]. In high-level amateur athletes, surgical excision enables successful return to sports participation at preinjury performance levels [6]. These athletes achieve normal function as measured by validated objective outcome measures, experience a significant reduction in pain, and report high overall patient satisfaction [6].

The open carpal tunnel approach is a successful technique for open excision of symptomatic ununited hook of hamate fractures due to its familiarity, ease of performance, excellent visualization, and low morbidity [8]. A modified surgical approach through Guyon’s Canal and the proximal ulnar border of the carpal tunnel allows for direct visualization of vital structures most at risk, including the motor branch of the ulnar nerve [16]. This modified approach preserves the nerve supply and blood supply to the hypothenar muscles [16]. Although hook of hamate regeneration can occur after fracture fragment excision [5], the procedure remains a standard of care for predictable, early return to play with a limited complication rate [14].

Anatomy & Pathophysiology

Bony Anatomy

The hamate is a carpal bone located in the distal row of the wrist [21, 28]. It consists of a body and a hook, or hamulus [28]. The hook of the hamate serves as an attachment site for the transverse carpal ligament [28] and provides an origin for both the flexor digiti minimi muscle [28] and the opponens digiti minimi muscle [28]. Articulations of the hamate include the lunate [21], capitate [21], triquetrum [28], and fourth metacarpal [21].

Ligamentous Anatomy

The capitohamate ligament is a thick structure measuring 5 × 5 mm in cross section [26] and possesses extensions to the third or fourth metacarpals [26]. The triquetrohamate ligament connects the triquetrum and the hamate [21, 26].

Neurovascular Anatomy

Guyon’s canal is bounded radially by the hook of the hamate and ulnarly by the pisiform [25]. Its boundaries also include the volar carpal ligament and transverse carpal ligament [25]. The canal contains the ulnar artery and nerve [25]. During hook of hamate excision, the motor branch of the ulnar nerve is a vital structure at risk [16]. In dorsal percutaneous approaches to the hamate hook, the dorsal branches of the ulnar nerve are at risk [18]. The carpus receives extraosseous blood supply from the terminal branches of the radial, ulnar, and anterior interosseous arteries [31]. Both the dorsal intercarpal arterial arch [31] and the basal metacarpal arterial arch [31] supply the distal carpal row.

Pathophysiology

In the athletic population, hook of hamate fractures may involve a pre-existing stress response in the bone [17]. High-energy single-impact hamate fractures are likely to occur in otherwise healthy bone without a pre-existing stress response [17]. Multiple direct traumas in sports can cause a stress fracture with sudden aggravation of symptoms leading to diagnosis [17].

Classification

Hook of hamate fractures are categorized based on several distinct clinical and mechanical characteristics.

Temporal Status: Fractures are classified as either acute or chronic [4].

Displacement: The injury pattern is defined as displaced or non-displaced [13].

Healing Status: Fractures are further classified as united or ununited [8].

Mechanism of Injury: Etiology is divided into two primary categories. Stress fractures result from multiple direct traumas in sports [17]. In contrast, high-energy single-impact injuries occur in otherwise healthy bone [17].

Clinical Presentation

In the athletic population, hook of hamate fractures and non-unions are associated with a pre-existing stress response in the bone [17]. This pathophysiology contrasts with high-energy single-impact fractures, which likely occur in otherwise healthy bone [17]. The etiology of these injuries is relevant to low-impact repetitive tight gripping activities [17]. Multiple direct traumas in sports can cause a stress fracture, with a sudden aggravation of symptoms leading to the diagnosis [17].

Investigations

MRI: Magnetic resonance imaging is the modality of choice for evaluating radiographically occult fractures of the hand and wrist [27]. Its primary advantages over CT and radiography include superior soft-tissue characterization, particularly of wrist ligaments and hand synovium, and the absence of ionizing radiation [27]. Modern systems operate at 1.5T or 3T, with 3T preferred for hand and wrist imaging due to its suitability for small fields of view [27]. High-resolution MRI aids in the evaluation of wrist ligament injuries [33]. A static magnetic field strength of at least 1.5 T using a dedicated wrist coil is recommended for analyzing interosseous, intrinsic, and extrinsic ligament insertions [33]. Higher field strengths provide a higher signal-to-noise ratio and shorter scan times [33].

MRI Protocol: Specific imaging planes are required for optimal ligament visualization. Volar extrinsic, SL interosseous, dorsal intercarpal, and LT ligaments are best visualized using 1 mm slices with no interslice gap in the coronal plane [33]. The DRC and intercarpal ligaments are best viewed on both coronal and sagittal images [33]. Oblique axial views along the longitudinal axes of these ligaments allow further analysis, especially when an injury is suspected [33]. Concomitant cartilage-sensitive imaging is integrative to assessment and surgical management, as cartilage integrity directly influences clinical decision-making [33]. Real-time MRI has been used to investigate dynamic instabilities, although its routine clinical use remains undetermined [33].

MRI Findings: MRI has an expanding role in acute wrist trauma evaluation [35]. Bone marrow edema may reveal radiographically occult fractures of the carpal bones or distal radius [35]. MRI detects additional marrow abnormalities in osteonecrosis, such as in the lunate (Kienböck disease) or scaphoid post-fracture [35]. Asymmetry of marrow signal in proximal and distal fragments of a fractured scaphoid suggests proximal pole ischemia [35]. Although MRI currently has a limited role in carpal tunnel syndrome evaluation, axial T2-weighted imaging clearly displays masses within the carpal tunnel and median nerve edema or swelling [35]. Tenosynovitis and tendon injuries in the wrist and hand can also be assessed with MRI [35]. Furthermore, MRI provides earlier detection of synovitis and erosive bone changes associated with rheumatoid arthritis than radiographs [35].

MRI Technique: Successful wrist study requires high-resolution images obtained with surface coil technique and high-field systems [35]. The examination should be directed at solving a specific clinical problem or question [35]. With proper technique, triangular fibrocartilage complex (TFCC) injuries can be demonstrated; perforations appear as linear defects or gaps filled with hyperintense fluid on coronal gradient-echo or T2-weighted pulse sequences [35]. Evaluation of scapholunate and lunotriquetral ligaments is more challenging, but with optimal technique and equipment, their integrity can be consistently assessed [35]. The addition of arthrographic contrast improves the visualization of these ligaments on MR images [35]. Extrinsic carpal ligaments can be identified with three-dimensional volumetric scanning and subsequent reconstruction, although MRI assessment of these structures currently has less impact on treatment [35].

CT: CT scanning enables the 3D analysis of carpal dysfunction [33]. By adding motion in real time (4D CT), this modality may hold future promise to noninvasively quantify the location and degree of injury and assist surgeons in planning treatment [33].

Dynamic Fluoroscopy: Dynamic fluoroscopy demonstrates abnormal motion between the scaphoid and lunate as well as changes in midcarpal joint kinematics [33]. Live imaging shows whether the DISI is reducible, providing valuable information for treatment planning [33].

Arthroscopy: Arthroscopy is considered by many to be the diagnostic intervention of choice for determining the degree of wrist injury [33]. It assesses cartilage condition (normal or degenerative), the ability to reduce the carpus, and any associated injuries [33]. The degree of intrinsic and extrinsic ligament injury can be identified from arthroscopic evaluation [33].

Treatment

Non-Operative

The provided evidence does not detail specific conservative management protocols such as weight loss, physical therapy, NSAIDs, or injections. Surgical intervention is presented as the primary effective method for managing acute and chronic hook of hamate fractures in professional baseball players [4].

Operative

Indications: Surgical excision is indicated for acute and chronic hook of hamate fractures, particularly in professional baseball players and high-level amateur athletes, where it serves as an effective management strategy with a low risk of minor complications [4]. It is also appropriate for non-displaced acute fractures and delayed unions of the hamate hook, which can be treated successfully with minimal morbidity [13].

Surgical Approach / Technique: A modified surgical approach through Guyon’s Canal and the proximal ulnar border of the carpal tunnel allows for safe excision of the hook of the hamate [16]. This approach provides direct visualization of vital structures most at risk, including the motor branch of the ulnar nerve, while preserving the nerve supply and blood supply to the hypothenar muscles [16]. Alternatively, a simplified dorsal approach with percutaneous fixation using a mini-Acutrak screw is effective for reduction and fixation, allowing rigid fixation of the fracture site [12]. Dorsal percutaneous cannulated mini-screw fixation is also a viable option for non-displaced acute fractures and delayed unions [13].

Outcomes and Return to Play: Surgical excision is safe and allows a relatively rapid return to play in most cases [2]. In baseball players, the procedure is associated with high return-to-play rates, typically occurring between 5 and 7 weeks after surgery [3]. Following treatment for hook of hamate fractures, return to play was documented for 94.5% (778/823) of patients [11]. In professional baseball players, 81% returned to the same or higher level after surgical excision [9]. Major League Baseball players can reasonably expect to return to their pre-injury performance levels following operative treatment [15]. For high-level amateur athletes, surgical excision results in a significant reduction in pain and is associated with high overall patient satisfaction [6].

Complications

Wound complications: Surgical excision of hook of hamate fractures in professional baseball players is associated with a low risk of minor complications [4]. Excision of the fractured hook provides a limited complication rate [14]. Dorsal percutaneous cannulated mini-screw fixation for fractures of the hamate hook is associated with minimal morbidity and complications [13].

Recovery

Light activity (weeks): The evidence does not specify a distinct week range for light activities such as desk work, driving, or light ADLs.

Full activity (months): Surgical excision of the fractured hook provides a predictable, early return to play [14]. In baseball players, this return is typically short, occurring between 5 and 7 weeks after surgery [3].

Complete recovery / outcome plateau (months): The provided evidence does not specify a month range for the stabilization of pain, strength, or final functional outcomes.

Rehabilitation protocol: The open carpal tunnel approach is characterized by familiarity, ease of performance, excellent visualization, and low morbidity [8]. No specific immobilisation duration, weight-bearing progression, or sling/brace removal timing is detailed in the evidence.

Functional milestones: In high-level amateur athletes, surgical excision allows for the achievement of normal function as measured by validated objective outcome measures [6]. This procedure also results in a significant reduction in pain [6].

Other Considerations: Surgical excision remains an effective method of management for both acute and chronic hook of hamate fractures in professional baseball players [4]. In most cases, the procedure is safe and allows a relatively rapid return to play [2]. Hook of hamate excision in baseball players is associated with high return to play rates [3]. The procedure carries a low risk of minor complications [4] and is associated with a limited complication rate [14]. The open carpal tunnel approach is a successful technique for open excision of symptomatic ununited hook of hamate fractures [8].

Key Evidence

  • [L4] In most cases, surgical excision as treatment for hook of the hamate fractures is safe and allows a relatively rapid return to play. [2] (10.1016/j.jhsa.2017.06.108)
  • [L4] Hook of hamate excision in baseball players is associated with high RTP rates and short RTP time, typically occurring between 5 and 7 weeks after surgery. [3] (10.1177/03635465261452783)
  • [L4] Surgical excision remains an effective method of management, with a low risk of minor complications for both acute and chronic hook of hamate fractures in professional baseball players. [4] (10.1016/j.jhsa.2021.03.015)
  • [L4] Hook of hamate regeneration can occur after fracture fragment excision. [5] (10.1016/j.jhsg.2024.08.008)
  • [L4] Surgical excision of hook of hamate fractures in high-level amateur athletes allows for successful return to sports participation at preinjury performance levels, achievement of normal function as measured by validated objective outcome measures, significant reduction in pain, and high overall patient satisfaction. [6] (10.1016/j.jhsa.2012.10.011)
  • [L4] Surgical excision of hook of hamate fractures in elite baseball players showed a very high rate of return to play within six weeks. [7] (10.1177/2325967121s00552)
  • [Paper] The study highlights the open carpal tunnel approach as a successful technique for open excision of symptomatic ununited hook of hamate fractures, because of its familiarity, ease of performance, excellent visualization and low morbidity. [8] (10.1016/j.injury.2014.05.008)
  • [L4] After surgical excision for hook of hamate fractures in professional baseball players, 84% were able to return to sport, with 81% returning to the same or higher level. [9] (10.1177/0363546520949204)
  • [L4] Surgical excision of hook of hamate fractures in elite baseball players showed a very high rate of return to play within 6 weeks. [10] (10.1177/23259671211038028)
  • [L1] Return to play was documented for 94.5% (778/823) of patients. [11] (10.1177/15589447241231303)
  • [L4] The authors conclude that the simplified dorsal approach with percutaneous fixation using a mini-Acutrak screw is effective for reduction and fixation of the hamate hook, allowing rigid fixation of the fracture site. [12] (10.3109/02844310801956714)
  • [L4] This pilot study demonstrates that non-displaced acute fractures and delayed union of the hamate hook can be treated successfully by dorsal percutaneous cannulated mini-screw fixation with minimal morbidity and complications. [13] (10.1142/s0218810412970039)
  • [L4] This study confirms that excision of the fractured hook provides predictable, early return to play, with a limited complication rate. [14] (10.1177/2325967118803090)
  • [L3] MLB players sustaining hook of hamate fractures can reasonably expect to return to their pre-injury performance levels following operative treatment. [15] (10.1123/jsr.2017-0071)
  • [L4] This modified approach allows direct visualization of the vital structures most at risk, including the motor branch of the ulnar nerve, unlike blind or unilateral approaches, and preserves the nerve supply and blood supply to the hypothenar muscles. [16] (10.1016/j.jhsa.2019.07.015)
  • [L5] [17] (10.1177/17531934241304249)
  • [L4] Surgeons should prepare a soft tissue protector beforehand or open a larger incision to clearly see and protect the dorsal branches of the ulnar nerve, as predrilling without protection can injure these branches. [18] (10.1177/17531934211035930)

See Also

References

[2] Return to Play and Complications After Hook of the Hamate Fracture Surgery. The Journal of Hand Surgery. 2017. DOI: 10.1016/j.jhsa.2017.06.108

[3] Return to Play After Hook of Hamate Excision in Baseball Players: A Systematic Review. The American Journal of Sports Medicine. 2026. DOI: 10.1177/03635465261452783

[4] Hook of Hamate Fractures in Major and Minor League Baseball Players. The Journal of Hand Surgery. 2021. DOI: 10.1016/j.jhsa.2021.03.015

[5] Hook of Hamate Regrowth After Surgical Excision: A Report of Two Cases. Journal of Hand Surgery Global Online. 2024. DOI: 10.1016/j.jhsg.2024.08.008

[6] Outcomes of Hook of Hamate Fracture Excision in High-Level Amateur Athletes. The Journal of Hand Surgery. 2013. DOI: 10.1016/j.jhsa.2012.10.011

[7] PAPER 14: Excision of Hook of Hamate Fractures in Elite Baseball Players: Surgical Technique and Return to Play. Orthopaedic Journal of Sports Medicine. 2022. DOI: 10.1177/2325967121s00552

[8] Surgical excision of ununited hook of hamate fractures via the carpal tunnel approach. Injury. 2014. DOI: 10.1016/j.injury.2014.05.008

[9] Performance and Return to Sport After Excision of the Fractured Hook of the Hamate in Professional Baseball Players. The American Journal of Sports Medicine. 2020. DOI: 10.1177/0363546520949204

[10] Excision of Hook of Hamate Fractures in Elite Baseball Players: Surgical Technique and Return to Play. Orthopaedic Journal of Sports Medicine. 2022. DOI: 10.1177/23259671211038028

[11] Return to Play After Hook of Hamate Fracture: A Systematic Review and Meta-Analysis. HAND. 2024. DOI: 10.1177/15589447241231303

[12] Simplified dorsal approach to fracture of the hamate hook with percutaneous fixation with screws. Journal of Plastic Surgery and Hand Surgery. 2010. DOI: 10.3109/02844310801956714

[13] DORSAL PERCUTANEOUS CANNULATED MINI-SCREW FIXATION FOR FRACTURES OF THE HAMATE HOOK. Hand Surgery. 2012. DOI: 10.1142/s0218810412970039

[14] Return to Play After Hook of Hamate Excision in Baseball Players. Orthopaedic Journal of Sports Medicine. 2018. DOI: 10.1177/2325967118803090

[15] Performance Outcomes After Hook of Hamate Fractures in Major League Baseball Players. Journal of Sport Rehabilitation. 2018. DOI: 10.1123/jsr.2017-0071

[16] A Modified Surgical Approach Through Guyon’s Canal and the Proximal Ulnar Border of the Carpal Tunnel Allows for Safe Excision of the Hook of the Hamate. The Journal of Hand Surgery. 2019. DOI: 10.1016/j.jhsa.2019.07.015

[17] Re: Campbell FC, Jones SW, Campbell DA. The aetiology of fracture and nonunion in the hook of the hamate. J Hand Surg Eur. 2024, 49: 1172-8. Journal of Hand Surgery (European Volume). 2024. DOI: 10.1177/17531934241304249

[18] Re: Massin et al. Safety and reliability of the dorsal percutaneous approach for non-displaced hook of hamate fracture: an anatomical study. J Hand Surg Eur. 2021, 46: 678–9. Journal of Hand Surgery (European Volume). 2021. DOI: 10.1177/17531934211035930

[21] Campbell S Operative Orthopaedics 4 Volume Set. NERVE INJURIES AT THE LEVEL OF THE HAND AND WRIST > ANATOMY.

[25] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 2Musculoskeletal Trauma Surgery > FRACTURES AND DISLOCATIONS OF THE DISTAL AND MID-FOREARM.

[26] Aaos Comprehensive Orthopaedic Review 3. Carpal Instability* > II. Anatomy and Biomechanics (See Chapter 92).

[27] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Anatomy, Evaluation, Clinical Examination, and Imaging > Imaging: Advances in Imaging of the Hand and Upper Extremity > Magnetic Resonance Imaging.

[28] Aaos Comprehensive Orthopaedic Review 3. Anatomy of the Hand and Wrist > VII. The Wrist.

[31] Campbell S Operative Orthopaedics 4 Volume Set. NERVE INJURIES AT THE LEVEL OF THE HAND AND WRIST > CIRCULATION.

[33] Green S Operative Hand Surgery. Advanced Imaging.

[35] Campbell S Operative Orthopaedics 4 Volume Set. WRIST AND ELBOW.

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b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.